Nordyne iQDrive Split System Heat Pump User manual

Installation Instructions
Split System Heat Pump
The iQ Drive heat pump operates as part of a larger intercommunicating system which provides temperature, air flow, and
humidity control for a residence or other similarly sized building. This system includes this outdoor unit, the dedicated iQ
controller (thermostat), and an iQ system-compatible indoor unit, typically an air handler with electric strip heat or a gas
furnace. The system will function only if these components are matched and intended for use within this system. A complete
list of compatible equipment by model and serial number is available in NORDYNE document 709031, iQ Field Wiring
Installation Instruction. Accessory equipment which may be used with this system includes humidifiers, electric or electronic
air cleaners, and U/V (ultraviolet) sterilizing lamps.
Refer to the System Operation section below for a complete description of how to use the various features of the system.
In addition to providing the means for operation, the controller also serves as the means for initial system configuration and
setup, and it provides a considerable amount of information for troubleshooting the system and diagnosing problems.
OTHER REFERENCE DOCUMENTS
• Installation instruction documents for indoor equipment (furnace or air handler, optional humidifier, etc.)
• iQ Field Wiring Installation Instruction, document 709031, provided in the iQ thermostat/controller kit
• iQ Thermostat/Controller User’s Manual, document 709063, provided in the iQ thermostat/controller kit
• local wiring and building codes
• Nordyne Application Guideline for Refrigerant Lines Over 75 Feet document 044B-0600
• iQ Zone System Zone Thermostat User’s Manual
• iQ Zone System Installation Instructions

2
TABLE OF CONTENTS
PREPARATION....................................................................................................................................................3
Slab Mounting..................................................................................................................................................3
Roof Mounting..................................................................................................................................................3
ELECTRICAL CONNECTIONS...........................................................................................................................3
Electrical Power Wiring ....................................................................................................................................3
Control Circuit Wiring.......................................................................................................................................4
iQ Zone Control Wiring ....................................................................................................................................4
Recheck Wiring................................................................................................................................................4
REFRIGERANT LINE CONNECTIONS...............................................................................................................4
Line Design and Routing..................................................................................................................................4
Brazing.............................................................................................................................................................5
System Evacuation..........................................................................................................................................5
Refrigerant Charging........................................................................................................................................5
Alternate Procedure for Charging a Heat Pump in Cooling Mode...................................................................6
Alternate Procedure for Charging a Heat Pump in Heating Mode...................................................................6
SYSTEM SETUP USINGTHE IQ CONTROLLER...............................................................................................6
General............................................................................................................................................................6
Screen Navigation............................................................................................................................................6
The Main Screen..............................................................................................................................................6
Installer Settings ..............................................................................................................................................7
System Configuration..................................................................................................................................7
Accessories.................................................................................................................................................8
Defrost Configuration ..................................................................................................................................8
Dealer Information.......................................................................................................................................8
Heat Off Delay.............................................................................................................................................9
Altitude Adjust .............................................................................................................................................9
Service Tests...............................................................................................................................................9
SERVICE INFORMATION Screens...................................................................................................................10
Other Configuration Entries ...........................................................................................................................11
Minimum Heat Pump OperatingTemp ......................................................................................................11
Auto Changeover Time..............................................................................................................................12
Date and Time...........................................................................................................................................12
Program Schedule vs.Nonprogrammable.................................................................................................12
Dehumidification........................................................................................................................................12
Humidity Settings ......................................................................................................................................12
Smart Recovery ........................................................................................................................................13
Zone Control..............................................................................................................................................13
System Operation: Quick Start.......................................................................................................................14
System Startup, Checkout, & Troubleshooting...............................................................................................15
SYSTEM DIAGNOSIS &TROUBLESHOOTING...............................................................................................16
Controller .......................................................................................................................................................16
Outdoor Unit Inverter .....................................................................................................................................16
Outdoor Unit Interface Board (right side small circuit board).........................................................................16
Outdoor Unit EXV Board (left side small circuit board)..................................................................................17
Indoor Unit Interface Board (in G6 iQ furnace kit or air handler) ...................................................................17
Indoor Unit EXV Board...................................................................................................................................17
Indoor Unit Constant CFM Motor Control Board............................................................................................17
Indoor Unit One or Two-Stage G7 Furnace Board.........................................................................................17
Indoor Unit iQ Modulating Gas Furnace Board..............................................................................................17
Airzone Control Board....................................................................................................................................17
iQ Zone System Configuration.......................................................................................................................18
Common Troubleshooting Issues...................................................................................................................18
MAINTENANCE.................................................................................................................................................19
FIGURES & DIAGRAMS.................................................................................................................................... 19

3
PREPARATION
BeforeproceedingwithinstallationofiQheatpumpequipment,
consultwiththedistributorandhomeownertoconfirmthatthe
equipment listed on the order is what was ordered, and that
it matches labeling on the equipment packaging.
Nextdetermine(includingconsultationwiththehomeowner)the
intended/preferred location for placement of the compressor/
outdoor coil unit. Unit envelope dimensions are shown in
Figure 1.
This heat pump is designed for outdoor installation only.
Unit placement must take into consideration the following
clearances: (a) A minimum of 18 inches must be provided
between each of the four sides and any solid barrier or wall
which might block free inlet air flow into the coil. A minimum
clearance of 36 inches is required between multiple units.
(b) The corner of the unit covered by the control access
cover must be clear enough to allow comfortable access by
a serviceperson. (c) The top of the unit must be open and
unobstructedtopreventrecirculationofoutdoorfandischarge
air,particularlyforairconditioningusage.Aminimumdistance
of 4 feet overhead clearance is recommended. Do not locate
the unit in a pit with high walls on all sides.
Locatetheunitawayfromoverhangswhichwouldallowwater
runoff or ice to fall directly onto the heat pump. Avoid placing
the unit near sidewalks or walkways to avoid possible icing
from defrost cycles. In low temperature climates, place the
unit where it is not directly in prevailing winds. Avoid placing
theheatpumpnearsleeping quarters or windows.Astheunit
goes through defrost cycles, a change in sound will occur.
Slab Mounting
The preferred unit mounting is on an outdoor slab (concrete
or plastic), on the ground, in an area with good drainage
unlikelytobeaffectedbyheavyrunoff,groundsettling,ordeep
snowdrift accumulation.The support slab should be level. If
thearea issubjecttoheavysnowfallordriftaccumulation,the
useof a snowstand is recommended as well. Makesurethat
the drain holes in the bottom of the unit are not obstructed.
Roof Mounting
The method used for roof mounting should be designed so
as not to overload roof structures nor transmit noise to the
interiorofthestructure.Refrigerantandelectricallinesshould
be routed through suitably waterproofed openings to prevent
leaking into the structure. Make sure that the roof structure
can adequately support the weight of the equipment.Consult
local building codes for rooftop installations.
After a location has tentatively been selected, trace routing
of new (or pre-existing) refrigerant lines (two), and power and
control wiring. See further discussion below.
• Maximum recommended length for refrigerant lines:100 ft.
• Maximum elevation difference, compressor base to indoor
coil base (compressor higher): 50 feet NOTE: An oil trap
is required for elevations exceeding 50 feet.
• Maximum elevation difference, compressor base to indoor
coil base (compressor lower): 50 feet NOTE: An oil trap is
required for elevations exceeding 50 feet.
• Refrigerant lines should NOT be buried. (in concrete or
otherwise)
• RefertoNordyneApplicationGuidelineforRefrigerantLines
Over 75 Feet document 044B-0600, for piping details
Oncetheaboveinformationhasbeenconfirmedandpotential
questions regarding location, refrigerant line routing, and
wire routing have been resolved, proceed with unpacking the
equipment. It is strongly recommended that inspection of the
hardware be performed prior to bringing it to the installation
site. Inspect for cosmetic as well as functional damage (such
as obvious holes or gaps in tubes and joints, cut or pinched
wires or wire insulation).
Verify that the iQ Drive®heat pump unit package includes the
following:
• Coil/compressor/control unit.
• Packetcontaininginstallationinstructionsandonefilter-drier.
NOTE: The thermostat/controller which is required for
system operation is part of a separately purchased kit.
ELECTRICAL CONNECTIONS
WARNING:
ELECTRIC SHOCK HAZARD
Disconnect all electrical power at main circuit box
before wiring electrical power to the outdoor unit.
Failure to follow these instructions may result in
electric shock or death.
Electrical PowerWiring
Electrical power wiring shall comply with the current
provisionsoftheNationalElectricalCode(ANSI/NFPA 70) as
supplementedbyapplicablelocalbuildingcodes.Theinstaller
shouldbecomefamiliarwiththewiringdiagrambeforemaking
electrical connections to the outdoor unit. An equipment
wiring diagram is included in this instruction and inside the
unit control panel cover. Refer to the unit rating label located
on the exterior of the control box cover for operating voltage,
minimumcircuitampacity,andmaximumfusesize. SeeTable
I for wire sizing.
COPPERWIRE SIZE - AWG (1% Voltage Drop)
Supply Circuit Ampacity SupplyWire Length - Ft
up to 50 51 - 100 101 - 150 151 - 200
15 14 10 8 6
20 12 8 6 4
25 10 8 6 4
30 10 6 4 4
35 8 6 4 3
40 8 6 4 3
45 6 4 3 2
50 6 4 3 2
Wire Sized based on N.E.C. for 60°C type copper conductors
Table 1. Copper Wire AmpacityTables

4
• A properly sized branch circuit and disconnect switch must
be installed where it is easily accessible and within line of
sight of the outdoor unit.
• Removethecontrolpanelcover.Routethepowerandground
wires (3 wires, including earth ground) from the disconnect
box to the unit. Use of outdoor shielded conduit (metal
lined Sealtite®) is required.The electrical conduit opening
is located on the lower left corner of the control box.
• Connect the power wires to L1 and L2 box lugs of the
contactor, and the ground wire to the grounding lug to the
leftofthecontactor.SeeFigures2and3.Onlycopperwires
should be used.
• Replace the control panel cover before applying power.
Control CircuitWiring
The heat pump is designed to operate with a 24 VAC Class
II control circuit. Control circuit wiring must comply with the
latest version of the National Electrical Code (ANSI/NFPA
70) as supplemented by local building codes.
In general, 24 VAC control power and communication bus
wiring must be run to interconnect the thermostat/controller,
theindoorunit,andtheoutdoorunit. The“hub”ofthisnetwork
and source of the 24VAC is located within the indoor unit (air
handler or furnace). Refer to iQ Drive System Field Wiring
Instructions, NORDYNE document 709031 shipped with the
controller, for connection of control wires to the indoor unit
and for description of other indoor field wiring, including to
the controller.
Five (5) wires must be run between the indoor unit and the
outdoor unit (2 for 24VAC power and 3 for communications).
Use one shielded cable (3 or more conductors) for
communications only, and a separate cable or pair of wires
for control power. Refer to wiring diagram Figure 4 andTable
II.
1. Passthe5 control wires into thehole in the lowerright side
of the control panel of the outdoor unit, into the separate
low voltage wiring compartment. See Figures 5 and 6.
2. Locate the 5 corresponding factory-wired leads with
stripped ends. Assure that each of these 5 wires (on the
factory wiring side of the wire connections) loops around
and through the “donut” (toroidal choke). Refer to Figure
7 which shows one wire making a single loop.
3. Connect each of the 5 field-run wires to its factory-wired
counterpart using a wire nut, as indicated in Figures 4, 5
and 6.
4. Replace the control panel cover before applying power.
IMPORTANT
It is critical that the wires meant to connect to 24
vaccontrolpower(RED&GRAY)arenotmistakenly
connected to the communication bus wires (YEL,
WHT,GRN).24 voltsapplied to the communication
bus will damage the equipment.
Communication Wiring
Indoor
Interface
Board
Terminal
Indoor
Interface
Board plug
wire color
Outdoor unit
wire color
Outdoor Interface
Board Terminal
(RHS circuit
board)
DX+ YEL YEL 3 pin 3 wire white
connector plug at
RHS circuit board
terminal
“INDOOR”
DX- WHT WHT
GND GRN GRN
Control Power Wiring
R (screw) [no factory
wire] RED “R” terminal screw
C (screw) [no factory
wire] GRY (contactor coil, RHS)
Table 2. ControlWiring to Outdoor iQ Heat Pump Unit
iQ Zone ControlWiring
For iQ Zone systems, field wiring is required to connect the
Airzone control board to the iQ communication bus and to
provide a ground connection for the separate zoning control
and communication network. Refer to the iQ Field Wiring
Instruction document provided in the iQ controllerkitformore
details.A 3-wire cable must be run from a splice point in the
iQ communication bus to the one 3-pin connector on the
Airzone control board.
RecheckWiring
Checkthatwireroutingiscorrectandconnections are secure
for all power and control wiring.
REFRIGERANT LINE CONNECTIONS
Line Design and Routing
Refrigerant lines must be connected by a licensed EPA
certified technician following sound established installation
practice.Once the heat pump location has been determined
andthe unit setinplace the refrigerantlines should be routed
and connected.
• Refrigerantlinesshouldfollowa direct path from the indoor
coil to the outdoor unit avoiding sharp bends. When lines
passthroughwalls,makesuretoproperlysealandsupport
them so that vibration is not transmitted to the structure.
• Refrigerant tubing should be supported in a manner which
assures that the tubing will not vibrate or wear as a result
of contact with sharp materials or edges during system
operation.
• Lines must be clean refrigeration-grade copper.
• Avoidremovingcaps andplugsfromtheheatpumporlines
until they are ready to be connected.
• Insulatethevaporlinewithrefrigerantlineinsulation¼”wall
thickness or greater.
Proper system performance and oil management depend on
properlyselectingtheliquidandvaporlinesizes.RefertoTable
III for the proper size of field supplied lines. The maximum
allowable refrigerant line length is 100 ft.

5
Vapor Line Liquid
Line
Line Set
Length up to 24 ft. 25 to 39 ft. 40 to 75 ft. 75 to 100
ft. up to 100 ft.
-024K Units 3/4 in.
(19 mm) 3/4 in. (19 mm) 7/8 in. (22 mm) 1 1/8 in. (29 mm) 3/8 in. (10 mm)
-036K Units 7/8 in.
(22 mm) 7/8 in. (22 mm) 1 1/8 in. (29 mm) 1 1/8 in. (29 mm) 3/8 in. (10 mm)
-048K Units 7/8 in.
(22 mm) 1 1/8 in. (29 mm) 1 1/8 in. (29 mm) 1 1/8 in. (29 mm) 3/8 in. (10 mm)
Table 3. Permissible Refrigerant Line Sizes
The maximum vertical elevation between the heat pump and
indoor coil is 50 ft. Systems that require more elevation will
need to have an oil trap installed in the vapor line. Refer to
Nordyne Application Guideline for Refrigerant Lines Over 75
Feet (document 044B-0600) for piping details.
A filter drier is supplied with the heat pump. It is required and
recommended that it be installed near the indoor coil.
It is recommended to replace existing refrigerant lines that
were previously used for an R-22 system. If the lines are not
replaced, they must be properly flushed by a licensed EPA
certified technician in accordance with the manufacturer’s
instructions and established procedures.
Brazing
Use the appropriate safety equipment while brazing. Items
such as gloves, safety glasses, proper ventilation, and a fire
extinguisher should be used.
1. Routetherefrigerantlinesfromtheindoorcoiltotheservice
valves on the heat pump. Avoid sharp radius bends and
turns.
2. Make sure that the vapor line is properly insulated for the
entire length of the run for maximum system efficiency.
Improperinsulationmayalsocreatecondensationandresult
in water damage to the equipment and building structure.
3. Removethevalvecoresfromtheheatpumpservicevalves.
Wrap the valves completely with wet rags to protect them
from overheating during the brazing operation.
4. Connect both the vapor and liquid lines. Tubes should be
round, de-burred and free of debris. Use a phosphorous
and copper or silver brazing alloy for the joints. Do not use
soft solder with a low melting point.
5. Connect the indoor lines according to the indoor unit
instructions. The indoor coil will require the same alloys
and wet rags to protect the sensors from excessive heat
on the refrigerant lines.
6. Allowtheservicevalvestocoolandreplacethevalvecores.
7. Leaktest the connections usinglowpressure drynitrogen.
System Evacuation
1. Connect the refrigerant gauge manifold to both the vapor
andliquid servicevalves.SeeFigure8.Connectthecenter
port to the vacuum pump.
2. Open both manifold valves and start the vacuum pump.
After a short time, it is recommended to close the manifold
valves and stop the vacuum pump to look for a rapid loss
of vacuum. Loss of vacuum indicates that there is a leak
in the system. Repeat the leak test if required.
3. Evacuate the system to at least 500 microns to remove
non-condensables and water vapor. Close the manifold
valves and remove the vacuum pump.
4. Connect the refrigerant tank to the center manifold port of
the gauge set. Pressurize the system enough to break the
vacuum.
5. Open both service valves by turning the valve stems ¼
turn counterclockwise. The stem will be in line with the
tubes. Replace the stem caps and tighten. Proceed with
Refrigerant Charging section.
WARNING:
The heat pump system contains liquid and
gaseous refrigerant under pressure. Adjustment
of refrigerant charge should only be done by a
qualified, EPA certified technician thoroughly
familiar with this type of equipment. Under no
circumstances should the homeowner attempt to
install and/or service this equipment. Failure to
complywiththiswarningcouldresultinequipment
damage, personal injury, or death.
Refrigerant Charging
NOTE: The unit must be charged at a fixed speed setting.
or this purpose the thermostat/controller needs to be wired
and powered prior to charging. Using the thermostat, go
to CHARGE MODE under SERVICE TESTS from the
INSTALLER SETTINGS menu, described later in this
document. Select CHARGE MODE to add or verify system
charge. In the CHARGE MODE screen, HEATING or
COOLING mode may be selected, depending upon which
mode of operation is more appropriate or convenient at the
time of charging. NOTES:
• Theheat pump is factory chargedforfield installed lines 15
ft.inlengthwiththematchingindoorequipment.Adjustments
to the refrigerant charge will be required for other length
and tube sizes. For lines longer than 15 ft with a 3/8” OD
liquid line, add 0.52 oz.per ft.
• Small variations in the temperatures and pressures are
normal due to differences in the installation.
• Large variations in the temperatures and pressures
could indicate incorrect charge or another problem with a
component in the system.
The preferred method of charging is by weighing in the
additional refrigerant required. If a charging scale is not
available, the next preferred charging method would be to
use the sub-cooling method in cooling mode.

6
MODEL: 2TON
(-024K) 3TON (-036K) 4TON (-048K)
Factory Charge
(for 15 ft.line set) 10.0 lbs (160 oz) 10.5 lbs (168 oz) 11.8 lbs (188 oz)
Additional Charge
for 50 ft.line set + 1.1 lbs (18 oz) + 1.1 lbs (18 oz) + 1.1 lbs (18 oz)
Additional Charge
for 100 ft.line set + 2.8 lbs (44 oz) + 2.8 lbs (44 oz) + 2.8 lbs (44 oz)
Table 4. Refrigerant Charge Quantities
Alternate Procedure for Charging Heat Pump in
CoolingMode(withoutdoortemperaturesabove
60 °F) Based on Subcooling:
While charging based on weight is preferred, this method is
acceptable. Use this method when the outdoor temperature
is 60°F or higher to verify the correct charge in cooling mode.
The indoor temperature should be between 70°F and 80°F.
1. Connectthegaugemanifoldtotheliquidandvaporservice
valves (Figure 8).
2. Start the system in CHARGE MODE, COOLING. Allow
the system to run 15 minutes to stabilize.
3. Recordtheliquid refrigerantpressureinpsigat theservice
valve.
4. Recordtheliquidrefrigeranttemperaturein°Fattheservice
valve.
5. Using the temperature value recorded, determine the
corresponding liquid refrigerant pressure from the upper
curve (for cooling) in the charging chart (Figure 9).
6. Ifthepressure measured in step3islessthanthe required
liquid refrigerant pressure determined in step 5, then
refrigerant needs to be added.
7. If the pressure measured in step 3 is greater than the
required liquid refrigerant pressure determined in step 5,
then the system is over-charged.
8. Add or remove charge from the system depending on the
measurements recorded. Allow the system to stabilize for
15 minutes before taking the next readings.
Alternate Procedure for Charging Heat Pump in
HeatingMode(withoutdoortemperaturesbelow
60 °F) Based on Subcooling:
Use this method when the outdoor temperature is 60°F or
lower to estimate the correct charge in heating mode. The
indoor temperature should be between 65° F and 75° F.
The preferred method of charging is by weighing in the
additional refrigerant required. If a charging scale is not
available,the correctchargecanbeestimatedbythismethod.
Refrigerant can be stored in the receiver and accumulators
and result in an over-charged system. If it is necessary to
usethismethod, followupserviceshould be scheduled when
the temperature is above 60°F, and then charge should be
verified in cooling mode.
1. Connectthegaugemanifoldto the liquid service valveand
suction service port located at the left side of the access
panel above the liquid service valve.See Figure 8.
2. Start the system in CHARGE MODE, HEATING.Allow the
system to run 15 minutes to stabilize.
3. Recordtheliquid refrigerantpressureinpsigat theservice
valve.
4. Recordtheliquidrefrigeranttemperaturein°Fattheservice
valve.
5. Using the temperature value recorded, determine the
corresponding liquid refrigerant pressure from the lower
curve (for heating) in the charging chart (Figure 9).
6. Ifthepressure measured in step3islessthanthe required
liquid refrigerant pressure determined in step 5, then
refrigerant needs to be added.
7. If the pressure measured in step 3 is greater than the
required liquid refrigerant pressure determined in step 5,
then the system is over-charged.
8. Add or remove charge from the system depending on the
measurements recorded. Allow the system to stabilize for
15 minutes before taking the next readings.
SYSTEM SETUP USINGTHE IQ CONTROLLER
IMPORTANT:
Itessentialthatthewires meant to provide24 volts
totheoutdoorunitarenotmistakenlyconnectedto
thecommunicationterminals. Checkagain before
you apply power!
General
Poweruptheentiresystemwith the iQcontroller(thermostat)
installedinitsbase.Thecontrollerwillbeofusetotheinstaller
for the following general purposes:
• Configuring the system using INSTALLER SETTINGS
screens (required)
• Running system service tests (recommended)
• Usingserviceinformationscreenstoexamineanddiagnose
system operation (very helpful, if needed)
• Setting options and features which are not typically used
or understood by the homeowner (recommended)
• Settingoptionsandfeatureswiththehomeowner’soversight
in an effort to train him/her (suggested)
The following descriptions of the controller apply specifically
to software Version 5.0. A summary of the controller menu
structureisprovidedinFigures10&11.NOTE:Thisguideline
is not intended to be a comprehensive substitute for proper
iQ Drive system training (required).
Screen Navigation
Moving between option categories on menu screens or
moving between possible values for any one option is done
using the and keys. The line or value with a dark
background behind the characters is considered “selected”.
In order to change a selected option in most screens, or to
save a changed value, use the key. Use the key to back
up into the previous screen in the menu/screen structure.
The Main Screen
The Main Screen is the normal display viewed on the
controller. It prominently shows room temperature and

7
operating mode (e.g., COOL or HEAT) in large numerals and
letters. Across the bottom line of the display are five words
or abbreviations (normally RH TEMP MODE FAN MENU)
which represent selectable entry points into the menus.The
user can always return to the main screen from any other
screen by repeatedly pressing the key.
76°
HUMIDITY
36
HEAT
FAN AUTO
MODERH FAN TEMP
3/13/09 12:18 PM
OUTDOOR
70
HEAT 62
COOL 85
MENU
For iQ Zone systems with zone control enabled, the Main
Screenwillappearslightlydifferent,asshownbelow.Thelocal
temperature reading is absent, and ZONE CNTL appears
under the operating mode.
HUMIDITY
36
COOL
FAN AUTO
MODE MENU
FAN
RH TEMP
1/19/09 10:00 AM
OUTDOOR
46
ZONE CNTL
Installer Settings
Using procedures explained in iQ Drive training, go to the
INSTALLER SETTINGS menu screen.
INSTALLER SETTINGS
SYSTEM CONFIGURATION
RESTORE DEFAULTS
DEALER INFORMATION
ALTITUDE ADJUST


ACCESSORIES
SERVICE TESTS
DEFROST CONFIG
HEAT OFF DELAY
IQ DRIVE REV 5.0
Other than in the splash screen displayed when power is
first applied to the controller, this is the only screen which
displays the controller software version number.
NOTE: It is important that any settings or service tests which
are appropriate be made at the time of system installation.
System Configuration
Any time“CONFIGURATION NEEDED”appears at the top of
theMainScreen,theusermustproceedthroughtheSYSTEM
CONFIGURATION screens, even if no changes to values or
options are necessary.This will occur when installing a new
thermostat or moving a thermostat to a different type of iQ
system. The outdoor unit should be powered up when
confirming or entering system configuration.
With the first line SYSTEM CONFIGURATION selected,
press the key to proceed through the system configuration
screens.Thenextscreen,titledSYSTEMCONFIGURATION,
provides a read-only summary of the configuration (as
detected,and otherwiseshowingeitherdefaultsor previously
configured information).
OUTDOOR SYSTEM
SYSTEM CONFIGURATION
1 STG GAS FURNACE
HEAT PUMP - IQ
INDOOR UNIT - OK

2 TON
WITH
BLOWER TYPE B
COMMUNICATION
OUTDOOR UNIT - OK

The words under OUTDOOR SYSTEM and WITH describe
the system components as automatically detected by the
controller. Both entries under COMMUNICATION should
show“OK”.If “CHECK” appears, it is an indication that either
communication wiring is incomplete or incorrect, or the
outdoor unit is not powered up.Proceed through subsequent
screens by using either the or key (indicated by“NEXT”).
The following table indicates the information that may be
or needs to be manually configured or confirmed by the
installer.(Information not listed is automatically determined.)
If necessary, check the ratings of the indoor unit before
proceeding.
Indoor Unit Items Requiring Manual Configuration
(or Confirmation)
Electric Heat Heat type, number of stages, staging
differentials, kW
G6 gas furnace Heat type, number of stages, 1st stage start
differential, furnace input rate, furnace rise. If
2-stage: 2nd stage differential
G7 single stage gas
furnace 1st stage start differential, furnace rise
G7 two stage gas
furnace 1st stage start differential, 2nd stage differential,
furnace rise
Modulating MQ gas
furnace Furnace rise
Table 5. System Configuration Entry Summary

8
For MQ modulating iQ gas furnaces only, an additional
screen titled “OUTDOOR SYSTEM” will appear after the
SYSTEM CONFIGURATION summary screen. “HEAT
PUMP-IQ”should appear on the second line;no other option
may be selected in this screen. Press the key to proceed.
OUTDOOR SYSTEM
HEAT PUMP - IQ
2ND STG DIFFERENTIAL
STAGES
CAPACITY (TONS)
-
-
-
AIR FLOW, CFM PER TON
-




Proceed through the subsequent configuration screens
either accepting or changing entries, until the INSTALLER
SETTINGS menu is displayed again. This is an indication
that configuration has been completed.
Accessories
Use the or keys to select ACCESSORIES. Press the
key to enter the accessories submenus and screens.This
setofscreens allowstheinstallertotrigger alerts(reminders)
when periodic maintenance is recommended for any of the
following accessories:
• Air filter
• Humidifier
• U/V lamp
• Air cleaner
If desired, set the maintenance alert timing for any of these
based on either hours of operation or calendar time. When
triggered by the passing of the selected time or operating
hours, the maintenance reminder message string will be
displayed on the top of the Main Screen. In addition, at the
baseoftheMainScreen“CANCELALERT”willappear.When
this is selected and the key is pressed, the maintenance
reminder message will be removed.
ACCESSORIES
AIR FILTER
UV LAMP
HUMIDIFIER
AIR CLEANER


MakingchangesorentriesunderACCESSORIESisoptional.
Dealer Information
Usethe or keystoselectDEALERINFORMATION. Press
the key to enter the dealer information summary screen,
and submenus and screens.This set of screens allows the
installer to enter text information which will be displayed on a
SERVICENEEDEDdisplayscreenifapersistentfaultoccurs.
The following items may be entered:
• Brand name (Maytag, Frigidaire, NuTone, Broan, Tappan,
Westinghouse, or custom)
• Model Number
• Contractor Name
• Contractor Phone Number
DEALER INFORMATION
BRAND NAME
CONTRACTOR NAME
MODEL NUMBER
911 - 393 - 7777


MAYTAG
FT4BI - 048K
JOE’S HVAC
CONTRACTOR PHONE
The entered dealer information summary screen accessible
here will be available for future reference by a serviceperson
(under INSTALLER SETTINGS > DEALER INFORMATION).
Entry of this information is optional.
Defrost Configuration
Usethe or keystoselectDEFROSTCONFIG.Pressthe
key to enter the screen which allows changes to:
• DEFROST TERMINATION TEMPERATURE. This is the
outdoorcoiltemperaturevaluewhich,whenreachedduring
thedefrostsequence,willsignaltheendofthedefrostphase
during which the system heats up the outdoor coil to melt
accumulated frost. (Default value is 75°F.)
• COIL DEFROST DELTA T. During heat pump heating
operation a defrost sequence will be triggered when
the outdoor coil temperature falls this amount below the
temperature it would operate at with a clear, unfrosted coil.
(Default value is 6°F.)
DEFR TERMINATION TEMP
6 DEG F


75 DEG F
COIL DEFROST DELTA T
DEFROST CONFIG


9
Under normal circumstances it is not necessary or advisable
to change these from their default values.
Heat Off Delay
If the system includes a G6 gas furnace, you may use the
or keys to select HEAT OFF DELAY. Press the key to
enter the screen which allows changes to the length of time
that the blower (indoor fan) will remain on after the furnace
flame is extinguished. Under normal circumstances it is not
necessary or advisable to change this from its default value
of 120 seconds.
Altitude Adjust
If the system includes an iQ modulating gas furnace, you
may use the or keys to select ALTITUDE ADJUST.
Press the key to enter the screen which allows changes to
the installation altitude (feet above sea level). This entry is
advisable for the modulating gas furnace. Refer also to the
furnace Installation Instructions.
Service Tests
You may use the or keys to select SERVICE TESTS.
Press the key to enter the screen which allows access to
a list of service tests. These tests provide an easy way for
the service person to operate the system in various modes
for operational confirmation and diagnostic troubleshooting
during installation startup. The following five options are
available in the submenu.
SERVICE TESTS
CHARGE MODE
AIR COND RUN TESTS
FURNACE TESTS


HEAT PUMP RUN TESTS
DISCRETE OUTPUTS
NOTE: While running the system from Service Tests is
convenient for some startup operations, much of the normal
faulthandlinganddiagnosticmessagefunctionalityisdisabled.
Withineachtestscreentheremaybemorethanoneentrywhich
canbechanged. Selectthedesiredentrytobemodifiedusing
the and keys. The line or value with a dark background
behind the characters is considered “selected”. Press the
key to allow changing the selected item (its dark background
will then blink). Set the desired value for the item using the
and keys, then press the key to save it.
The following is a brief description of the SERVICE TEST
categories.NOTE:WithiQZonesystemstheremaybeadelay
before the test begins, as all zone dampers open.
CHARGE MODE – Runs the system at the proper speed for
checkingandadjustingrefrigerantcharge. Selectthemodeas
HEATING or COOLING, then change RUN from OFF to ON.
The screen backlight will blink red. The user may navigate
to other screens (e.g., SERVICE INFORMATION) during the
process until ON in the CHARGE MODE screen is changed
back to OFF and saved. The red blinking backlight serves as
a reminder that the unit is operating in an abnormal (service)
mode. Select OFF (from the list that includes ON and OFF)
and SAVE ( ) when finished.
FURNACE TESTS – Runs the system at the selected fire
level to allow confirmation of proper operation. The screen
backlight will blink red. A short list of instructions (reminders)
isprovided.SelectSTARTtorunasinglestagefurnace.Select
LOFIRE or HI FIREto runatwostage furnace.Theuser may
navigate to other screens (e.g., SERVICE INFORMATION)
during the process. The red blinking backlight serves as a
reminder that the unit is operating in an abnormal (service)
mode. Select DONE (from the list that includes LO FIRE, HI
FIRE,START,STOP)andSAVE( )whenthetestiscomplete,
before leaving the screen for the last time.
AIR COND RUNTESTS and HEAT PUMP RUN TESTS – In
these screens the unit can be made to run at a fixed speed
regardless of room temperature. RUN can be changed
between OFF, MAX (speed), INTERMED(iate speed), and
MIN (speed). MAX speed is the same as that used in charge
mode. The screen backlight will blink red when anything but
OFF is selected and saved.The user may navigate to other
screens (e.g., SERVICE INFORMATION) during the process
until RUN in this screen is changed back to OFF and saved.
The red blinking backlight serves as a reminder that the unit
is operating in an abnormal (service) mode. This screen is
primarily intended for test agency usage. Heat pump run
tests apply only to heat pump units. Select OFF and SAVE
() when finished.
ForiQheat pumpsthecapabilitytoforceadefrostisavailable.
As indicated on the HEAT PUMP RUN TESTS screen, this
featuremayonlybeusedwhenMAXspeedhasbeenselected.
To perform a sample defrost while a MAX speed heating run
testisrunning,pressthe keytoselectDEFROSTNOW,then
press the ( ) key to begin the defrost.The defrost sequence
will proceed, including use of auxiliary heat while heating the
coilandthe8minutepost-defrostcoiltemperaturecalibration.
Only use this feature if the outdoor conditions are typical
heating conditions.Do not force a defrost before the system
has operated in heating for several minutes first.
DISCRETE OUTPUTS – When the unit is off, this screen
allows the user to operate certain relay-driven outputs in the
system for diagnostic purposes: humidifier (on the indoor
interface board or blower control board), reversing valve (on
the outdoor interface board), indoor coil EXV (on the indoor
interfaceboard orblowercontrolboard),outdoor coilEXV(on
the outdoor interface board), and crankcase heater (on the
outdoor interface board). More than one of these can be set
to ON at the same time. Leaving the DISCRETE OUTPUTS
screen will shut all of the listed outputs off.

10
SERVICE INFORMATION SCREENS
Typically, when anyof these service tests isbeingperformed,
theservicepersonshouldcheckoperationvisually,withspecial
instrumentation(ifavailable),andviewoperationaldataonthe
SERVICE INFORMATION screens.Refer to iQ Drive training
information for how to view these screens.
SERVICE INFORMATION
FAULT STATUS
FURNACE STATUS
OUTDOOR FAN STATUS
CALIBRATION DATA
PREVIOUS
SELECT OPTION
COMPRESSOR STATUS
INDOOR FAN STATUS
TEMPERATURE STATUS
CLEAR FAULT HISTORY
COMMUNICATION DATA
CAPACITY CONTROL
ZONING DATA
DEFROST STATUS
Most of the items on the SERVICE INFORMATION menu are
self-explanatory by title. Some key features are the following
(by item name):
FAULT STATUS – The top entry is ACTIVE FAULT. This
should show NO FAULT unless the last fault detected has
not cleared after its 5 minute lockout period, or the fault
condition still exists. The remainder of the screen shows a
history of previous faults or conditions detected, with military
time and date stamps for each. (Having the correct time and
date configured is important in making this list useful.) Use
the key to view the remainder of the last (most recent) 10
faults logged.Generally, fault logging is not functional during
Service Tests.
FAULT STATUS
ACTIVE FAULT
1
2

LOW PRESSURE SWITCH
FAULT HISTORY
LOW PRESSURE SWITCH
FLT 23:59 11/14/09
OD UNIT COMM FLT
NO FAULT
#20 23:59 10/31/09
3

COMPRESSOR STATUS – This screen should confirm the
configured size as MODEL NUMBER (20 = 2 tons, 30 = 3
tons,etc.)Withcorrectconfigurationonly 20, 30, or 40 should
appear here. LOW PRESSURE SW shows the state of the
low pressure switch. Any COMPR ERROR CODE number
(normally 0) will be logged in the FAULT STATUS screen in
more easily understood wording. The displayed information
is read from the outdoor unit.
OUTDOORFAN STATUS–AnyFAN ERRORCODEnumber
(normally 0) will be logged in the FAULT STATUS screen in
more easily understood wording.
INDOOR FAN STATUS – The contents of this screen varies
depending on which type of blower motor is in the equipment
and whether or not iQ Zone is in use.Much of the information
is not useful to the installer.
TEMPERATURESTATUS–Thisscreenlistsalltemperatures
measured by the iQ system. TEMP AT TSTAT is the local
temperature used for control (when zoning is not enabled),
anditdisplaysonedecimalplacewithoutshowingthedecimal
point (e.g., 704 = 70.4°). In iQ Zone systems, a supply duct
temperature sensor is required, and its reading is displayed
here.
CLEAR FAULT HISTORY – It is recommended that any faults
thatappearedduring and asaconsequenceofinstallationbe
cleared out before leaving.
CALIBRATIONDATA–APanasonicblowercanberecalibrated
any time from this screen by pressing the key.This may be
doneifasignificantchangehasbeenmadetoblowerdischarge
ductingordamperusage.Thisscreenisnotnormallyusefulto
an installer.Data is not displayed for type “B” blower motors.
COMMUNICATIONDATA–Thisimportantscreenindicatesthe
status of communication with all elements on the iQ bus. All
shouldshowOK.Ifnot,investigateandresolvecommunication
wiringissues.IniQZonesystemsonly,theentryZONEBOARD
willbedisplayed,representingthemainAirzonecontrolboard.
COMMUNICATION DATA
BLOWER

OK
ID INTERFACE BD
OUTDOOR BAD
OK
OD INTERFACE BD BAD

11
DEFROST STATUS –This screen confirms that a heat pump
is in defrost and provides detailed information helpful to
understand (a) the status of an in-progress defrost cycle and
(b) conditions which may trigger the next defrost cycle.It also
indicates the state of the reversing valve (ON for cooling or
during defrost heating). (Refer to training.)
DEFROST ON
TIMERS:
TARGET STEP
OD COIL TEMP

DEFR STG
COMP 210
OUTDOOR TEMP
ID COIL TEMP
DEFROST COIL T
CLEAR COIL DT
DEFROST STATUS
RV ON
7
9
DEFR 210
33
72
66
3
24
F
F
F
F
F
ZONING DATA – This screen and its sub-screen ZONE
MODULE STATUS (accessible by pressing the key when
in the ZONING DATA screen) provide important information
to help confirm proper installation and setup of an iQ Zone
system.Amongotherthings,theZONINGDATAscreenshows
the numbers of the zones which are active (open and in use)
and the weighting assigned to each zone.
Pressthe keytoviewZONEMODULESTATUS.Duringzone
systemsetupthisscreenwillindicatewhichzonemodulesare
detected in the zone system communication network, which
zone each module is associated with, and any damper motor
issues.After installation of an iQ Zone system, this screen is
essential to confirm that all module assignments have been
made and detected correctly.
ZONING DATA
PREVIOUS
12345678
ZONES ACTIVE
AZF
HEAT DEMAND
COOL DEMAND
MODE
ZONE FLAGS
ZONE WEIGHTS
ZONE 1 40
ZONE 2 25
ZONE 3 15
ZONE 4 10
ZONE 5 10
ZONE 6 0
ZONE 7 0
ZONE 8 0
DETAILS
OUTPUT
00100001
65
-90
400
COOL
10000001
NF
CAPACITY CONTROL – This screen contains information
primarily relating to the status of the outdoor iQ unit. Target
andactualspeedsareshownforthecompressor,outdoorfan,
and indoor blower. The line above “ROOM TEMP” displays
helpfulsystemstatusmessages,including whether or not the
system is dehumidifying during cooling.
HEAT PUMP HEATING
USED DEMAND
SP 700
COMP RPM

ROOM TEMP
ACT
STEP
OD FAN RPM
OVERRIDE ACTIVE?
CAPACITY CONTROL
704 F
698 F
8
2636
NO
-6 F
8
2640
MODSP
TARG
1042 1050
ID FAN RPM 910 900
Other Configuration Entries
The following settings in the controller fall into the following
categories:
• options and features which are not typically used or
understood by the homeowner, and should be examined
and considered for adjustment if desired by the installer,
including:
- minimum heat pump operating temperature
- autochangeover time
• settingswhicharerecommendedtobedonebytheinstaller,
including:
- setting date and time
• optionsandfeatureswhicharerecommendedtobesetwith
the homeowner’s oversight, including
- selection of programmable schedule versus non-
programmable
- usage of dehumidification (enabled by default)
- humidity settings
- usage of Smart Recovery (disabled by default)
• further features which the installer may demonstrate to
the homeowner, including
- schedule, including setback temperature settings
- usage of holds
- fan options
- temperature units (°F or °C)
- USA clock or military time (12 or 24 hour)
• settingsandfeatureswhichareuniquetotheiQZonesystem
(if installed) which should be explained to the homeowner,
including
- how to disable or re-enable zone control
- ventilation (fan) options
- settings typically made at the iQ controller which do not
applywithaniQZonesystem(withzonecontrolenabled)
- settings associated with an iQ Zone system (with
zone control enabled) which are entered at local zone
thermostats, not from the iQ controller
The above settings are described below:
Minimum Heat Pump OperatingTemperature
Thisistheoutdoortemperature(measuredbeneaththeoutdoor
unitcontrolpanel)belowwhich,whenheatingiscalledfor,the
heat pump will not operate and backup heat means (electric
heat or gas furnace) will take over. The ideal temperature
setting is the “balance point” below which it would be more

12
economical torun thebackupheat ratherthan theheat pump.
Thedefaultandminimumvalueforthisparameteris12°F.Once
the outdoor temperature rises above this setpoint, the heat
pumpwill bepermittedtooperateagainafterthedemandhas
been satisfied and backup heat has shut off.(Determination
of the balance point is not simple and depends on a variety of
local factors, including the price of electricity and gas at any
particular time.) To modify the value, perform the following:
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. Use the or key to select SETTINGS, then press the
key to enter the Settings menu.
3. Use the or key to select OPTIONS, then press the
key to enter the Options screen.
OPTIONS
PROGRAM SCHED USAGE
60
ON
4 SCHED EVENTS/DAY
DEHUMIDIFICATION
AUTO CHANGEOVER TIME
SMART RECOVERY
OFF
HEAT PUMP USAGE LIMIT



MINUTES
NOT BELOW 14F
4. Use the or key to select the value under HEAT PUMP
USAGE LIMIT, then press the key to allow changing the
setting.
5. Use the or key to change the value (2°F increments),
then press the key to save the setting.
6. Pressthe keymultipletimestoreturntotheMainScreen.
Auto Changeover Time
ThisadjustmentenablesAUTOmode,whichallowsthesystem
to automatically switch between heating and cooling without
havingtotouchthecontroller.Autochangeovertimeisthedelay
(minimum time) between the end of cooling operation and
the beginning of heating operation (or the reverse).DISABLE
removesAUTOasanavailablemode.Otherwise,thetimemay
be selected from 15 to 120 minutes (default 60 minutes).To
modify the value, perform the following:
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. Use the or key to select SETTINGS, then press the
key to enter the Settings menu.
3. Use the or key to select OPTIONS, then press the
key to enter the Options screen.
4. Use the or key to select the value under AUTO
CHANGEOVER TIME, then press the key to allow
changing the setting.
5. Use the or key to change the value, then press the
key to save the setting.
6. Pressthe keymultipletimestoreturntotheMainScreen.
Date and Time
Settingdateand time earlyin the installationprocessnotonly
saves the homeowner from having to do it, but provides an
accurate time and date stamp for any faults logged (during
installation checkout, for example) in FAULT HISTORY. By
default, the clock is in 12 hour format. This may be changed
on the OPTIONS menu screen (see either of the above two
items).DaylightSavingTimeisautomaticallytakenintoaccount
but may be disabled from the SET DATE AND TIME menu
screen. To set date and time, perform the following:
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. SET DATE AND TIME will be selected. Press the key
two times.
3. Enter the year, month, day (date), hour, and minute on
consecutive screens. Use the or key to change any
value, and press the key to advance to the next. After
setting the minutes value, press the key to save the
complete setting.
4. Pressthe keymultipletimestoreturntotheMainScreen.
Program Schedule versus Nonprogrammable.
While using “setback” program schedules are advisable to
take advantage of potential economic and energy savings,
some homeowners still prefer to perform setpoint adjustment
by exclusively using the and keys. The following setting
providesthenonprogrammableoptionortheoptionfordifferent
numbers of events per day (2 or 4) on the program schedule.
To set the program schedule option, perform the following:
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. Use the or key to select SETTINGS, then press the
key to enter the Settings menu.
3. Use the or key to select OPTIONS, then press the
key to enter the Options screen.
4. The value under PROGRAM SCHED USAGE will be
selected. Press the key to allow changing the setting.
5. Use the or key to change the value between “NON
PROGRAMMABLE”,“4SCHEDEVENTS/DAY”,“2SCHED
EVENTS/DAY”,and“2EVENTS/DBUSINESS”.Thenpress
the key to save the setting. (The difference between “2
EVENTS/D BUSINESS” and “2 SCHED EVENTS/DAY”
is only the name given to the time blocks within a daily
schedule.)
6. Pressthe keymultipletimestoreturntotheMainScreen.
Dehumidification
When dehumidification is enabled (as it is by default),
the system will (depending upon the conditions) suspend
responding to room temperature and lower blower speed to
enhance removal of moisture from the air circulating through
the indoor coil. When operating in this manner, the unit will
run cycles of 10 minutes dehumidifying, 5 minutes normal
cooling (adjusting capacity). See also setting the humidity
setpoints in (6) below.To change the dehumidification option,
perform the following:

13
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. Use the or key to select SETTINGS, then press the
key to enter the Settings menu.
3. Use the or key to select OPTIONS, then press the
key to enter the Options screen.
4. Use the or key to select the value under
DEHUMIDIFICATION, then press the key to allow
changing the setting.
5. Use the or key to change the value between “ON”
(the default) and “OFF”, then press the key to save the
setting.
6. Pressthe keymultipletimestoreturntotheMainScreen.
Humidity Settings
Separatesetpointsforhumidificationanddehumidificationare
availableinunitsofpercentRH(relativehumidity).Thehumidify
setpoint only is relevant if optional humidifier equipment has
been installed and connected to the system (the 24 vac
“H” output – See the Field Wiring Installation Instructions).
The installer should clarify for the homeowner that priority
is given to cooling over dehumidifying, so the ability of the
system to satisfy the RH setpoint(s) depends on a variety of
conditions. For example if the cooling load causes the unit
to run at an intermediate speed or higher, the effectiveness
of dehumidification is increased.
Humidification can operate when the system is heating
or the fan is set to Manual (ON) with the compressor off.
Dehumidification can operate only when the system is
cooling mode, the dehumidification option is enabled, and
room temperature is close to the setpoint.To set the humidity
setpoint(s), perform the following:
1. From the Main Screen, press the or key to select RH
at the bottom of the screen, then press the key to see
the Humidity screen.The current setpoints are displayed.
2. As indicated at the bottom of the screen, press the key
to enter the Humidity Settings screen.
HUMIDITY SETTINGS
45%
HUMIDIFY
DEHUMIDIFY



50%
3. Use the or key to select the RH setting to change,
then press the key to allow changes.
4. Use the or key to change the RH setting then press
the key to save the setting. The configurable ranges for
HUMIDIFY and DEHUMIDIFY are different, and changing
one may push the other so that a minimum of 5% is
maintained between the settings. The humidify setpoint
canbesetintherange30 to 45% in increments of5%.The
dehumidify setpoint can be set in the range 35 to 70% in
increments of 5%. Press the key to save any changes
5. Pressthe keymultipletimestoreturntotheMainScreen.
Smart Recovery
When Smart Recovery is enabled, the system will start
changing the cooling or heating setpoint in advance of a
schedule change so that the room temperature is at or near
thesetpoint of the subsequent schedule timeblockwhenthat
time block begins. It only applies if the subsequent cooling
setpointislowerorheatingsetpointinhigher.Also,ifPROGRAM
SCHEDUSAGEissettoNONPROGRAMMABLE,thisoption
doesnotapply.To change thesmartrecoveryoption,perform
the following:
1. From the Main Screen, press the or key to select
MENU at the bottom of the screen, then press the key
to see the Main Menu.
2. Use the or key to select SETTINGS, then press the
key to enter the Settings menu.
3. Use the or key to select OPTIONS, then press the
key to enter the Options screen.
4. Use the or key to select the value under SMART
RECOVERY, then press the key to allow changing the
setting.
5. Use the or key to change the value between “OFF”
(the default) and “ON”, then press the key to save the
setting.
6. Pressthe keymultipletimestoreturntotheMainScreen.
Zone Control
Theinstallershouldprovidetothehomeowner(s)adocument
or diagram which lists or shows (a) the rooms assigned to
each zone number, (b) the weighting assigned to each zone,
(c)thezonemodulenumberassociatedwitheachsupplyvent.
CurrentdateandtimemustbesetintheiQthermostat/controller
since they will be transmitted to, and continually updated in
the local zone thermostats.The Security Lockout feature will
not prevent changing settings in local zone thermostats in an
iQ Zone system.
Temperature units (Fahrenheit or Celsius) can be changed
as follows: Locate the set of eight microswitches on the iQ
Zone main circuit board. Disconnect control power from the
circuit board.Set microswitch #6 up (on) for °F, down (off) for
°C. Reconnect control power.
Itisrecommendedfortheinstallertoinstructthehomeowner(s)
on the following:
For zoning operation, Operating Mode (COOL, HEAT,
AUTO, E-HEAT, or OFF) must be selected from the iQ Drive
thermostat/controller as with non-zoning systems. However,
the temperature setpoints that will be used are entered and
stored at the local zone thermostats. With iQ Zone systems,

14
all settings made in the iQ thermostat/controller dealing
with temperature setpoint (temporary hold, vacation hold,
permanent hold,time schedule,smart recovery) do not apply
unless zone control is disabled.Similar features are provided
and controlled at each zone independently, from the local
zone thermostats. For example, Manual Setpoint Control
replacesTemporaryHold,AutomaticSetpointControlreplaces
time schedules, and Sleep Mode replaces Smart Recovery.
See the iQ Zone System ZoneThermostat User’s Manual for
information on these alternative features. With the iQ Zone
system a single setpoint is used for both heating and cooling,
as opposed to the standard non-zoning system, which uses
a different setpoint for each.
Zone Control is enabled by default if the system is equipped
with and wired for iQ Zone (the normal operating situation).
However, zone control operation can be disabled by choice,
or it may be automatically disabled if there is a problem
detectedwithit.Tomanuallydisablezonecontrolwhenzoning
is already enabled:
ZONE CONTROL
ENABLE
MODIFY
PREVIOUS
SAVE
ZONE CONTROL
1. From the Main Screen select MENU using the
or button.
2. Press the button.
3. Select SETTINGS using the or button.
4. Press the button.
5. Select ZONE CONTROL using the or button.
6. Press the button.
7. Press the or button to change ENABLE to DISABLE.
8. Press the button to save the setting.
Torestorezonecontrol(whenthezoningsystemcomponents
are functioning properly), follow the above sequence, but in
step 7 change DISABLE to ENABLE.
iQ Zone offers two types of ventilation that can be turned on
when the cooling or heating systems are not running:
• To deliver air to some but not all zones when not heating
or cooling, use the zone ventilation feature that is set up at
the individual zone thermostats. See the iQ Zone System
Zone Thermostat User’s Manual for information on how to
setupzone-by-zoneventilation. FromtheFANMENU,enter
the VENTILATION SPEED screen in the iQ thermostat/
controller to select or modify the relative speed to be used
when this type of ventilation is operating.
• To use the fan to deliver air to all zones when not heating
or cooling, set the Fan Mode to ON.The Intermittent Fan
featuredescribedearlierwillalsooperate,servingallzones.
Refer to the iQ Drive User’s Manual for other details relating
to zone control operation.
System Operation: Quick Start
Thefollowingisasummaryofthesequencefortypicaloperation
of the system.
1. Set the date and time (if not already set).
2. Check the program schedule for desired “setback”, and
modify if desired.
3. From the main screen, check/set the Fan operating mode:
• AUTO operates the fan (indoor blower) when the unit is
cooling or heating. This is the “normal” setting.
• ON operates the fan at the selected speed at all times.
Theselected speedmaychangewhen thecompressor,
electric heat, or furnace is operating.
• PROGRAMMED FAN operates the fan in AUTO or ON
as specified in the program schedule.
4. From the main screen, check/set the Mode:
• COOL runs the heat pump as an air conditioner using
thecoolingsetpoint.(WithiQZone,zonecontrolenabled,
there is a single setpoint for both heating and cooling.)
• HEATattemptstoruntheheatpumptoprovideheatusing
the heating setpoint. If (a) the outdoor temperature is
belowtheHeatPumpUsage Limit,or(b)theheat pump
cannot satisfy the load, or (c) the heat pump is disabled
due to a fault, auxiliary (backup) heat will operate. If
backup heat is electric strip heat, it may operate along
with and supplementing the heat pump. If backup heat
is a gas furnace, the furnace and heat pump will not
operate at the same time (except during defrost).(With
iQZone,zonecontrolenabled,thereisa singlesetpoint
for both heating and cooling.)
If the outdoor coil temperature is below 35°F, demand
defrost is enabled. Under these conditions, a first time
defrost will occur after approximately one half hour of
compressor operation.Subsequent defrost cycles may
be triggered by a drop in outdoor coil temperature or by
a maximum time between defrosts of 6 hours.Refer to
training material for details.
• E HEAT will run the auxiliary heat (electric strip heat or
gas furnace) using the heating setpoint and disable the
heat pump.
• OFF terminates any of the above.
NOTE: Equipment may not shut off immediately after
switching to OFF due to various system limitations.
Once put into the OFF mode, wait until the furnace or
compressorhasshutoffbeforeselectinganothermode.

15
5. ForsystemswithoutiQZone,adjust the operatingsetpoint
if desired using a temporary hold (pressing the or key
when the Main Screen is displayed).With iQ Zone, zone
controlenabled,adjusttheoperatingsetpointforeachzone
individuallybytouching the or icon. (Referto iQ Zone
System Zone Thermostat User’s Manual for details.)
System Startup Checkout &Troubleshooting
The following is a summary of the sequence for typical first
operation to check out the system. Reference is made to
INSTALLER SETTINGS and SERVICE INFORMATION
described above.
1. Install system hardware as described in the individual
component installation instructions.
2. Install power and control wiring to all system components,
including the controller, in accordance with the iQ Field
Wiring Installation Instructions.
3. Performpre-chargeevacuationoffield-installedrefrigerant
lines as described in preceding sections.
4. For iQ Zone systems, first apply 12 volt dc power to the
zonecontrolboardwiththeprovidedAC/DCconverter.Apply
electrical power to the system (including the heat pump).
The controller screen display backlight should come on,
and the “iQ” splash screen should appear. If it does not,
trace the 24 vac control power to the “R” terminal on the
thermostat. CONFIGURATION NEEDED should appear
on the top line of the Main Screen (unless the thermostat
had been previously used on a similar iQ system).
5. Proceed with System Configuration from the INSTALLER
SETTINGS menu (described above). On the SYSTEM
CONFIGURATION screen verify that the using size (2 ton,
3 ton, or 4 ton) is correct as indicated. If the wrong value
is shown, the inverter may require re-initialization.Contact
the service representative of the distributor in this case.
Onthesamescreen,theentriesunderCOMMUNICATION
should be followed by “OK”. If “CHECK” appears for a
communicationitem,gototheCOMMUNICATIONSTATUS
screen (in the SERVICE INFORMATION menu, described
above), and view which elements are not communicating.
Traceandcheckthethreecommunicationwiresthroughout
thesystem.If isolatingacommunicationproblemprovesto
bedifficult,itmaybeusefultodisconnectallcommunication
wires except those which link the thermostat and the non-
communicating element.
6. IfCOMMUNICATIONSTATUSwasnotcheckedduringthe
previous step, check it at this time. All listed items should
show a status of “OK”. If any show “BAD”, determine the
source of the problem as indicated in the previous step,
and resolve.
7. For iQ Zone systems only, the main screen should appear
with no temperature reading, and “ZONE CTRL” should
appearbelow“OFF”. Ifthisis notthecase,gotothe ZONE
CONTROLscreenfromtheSETTINGSmenu,andchange
the zone control option to ENABLE. If ZONE CONTROL
doesnotshowuponthat menu,theiQcontrollerhasnever
communicatedwiththezonecontrolboard,andpowerand
communicationwiringto thezonecontrolboardneedto be
checked. If the main screen reverts to back to the zoning-
disabled screen (showing room temperature), power and
communication wiring to the zone control board need to
be checked.
8. Set date and time as described above.This will provide a
“time stamp” for any fault which may arise during system
checkout.
9. If the installation includes a new gas furnace, check out
its operation first. This may be best accomplished from
FURNACE TESTS under SERVICE TESTS from the
INSTALLER SETTINGS menu (see above). Follow steps
instructionsprovidedinthefurnace’sinstallationinstructions.
Be sure to verify blower operation during the test.
10.If the outdoor temperature is above 60°F (14°C), test the
refrigerant system running in cooling mode first. If the
outdoor temperature is between 12° and 60°F (-11 and
14°C),testtherefrigerantsystemrunninginheatingmode
first.ThismaybestbeaccomplishedfromCHARGEMODE
underSERVICETESTSfromtheINSTALLERSETTINGS
menu. Followtherefrigerantchargeadjustmentprocedure
explained above. Note that if a fault is determined in the
outdoor equipment, the backup heating means (electric
strip heat or gas furnace) will start instead.
11.When charge adjustment is completed (if required), run
the heat pump in both cooling and heating modes. This
mayalsobe done usingSERVICETESTSalthoughsome
diagnostic messages are disabled in that method.
12.Check the FAULT STATUS screen (described above)
for any faults logged during the startup process. Any
message listed as “ACTIVE FAULT” refers to a condition
which either still exists or occurred within the preceding 5
minutes. Every fault or notification should appear in the
FAULT HISTORY log which starts on the same screen.
The last 10 faults to have occurred are retained in this
list. Each new item pushes other logged faults down in
the list. The second line associated with each of the 10
entries includes the time and date of detection. While
the wording of fault messages is intended to provide a
reasonable indication as to the responsible condition, the
informationconveyedbytheabbreviatedwordingislimited.
Consequentlytheinstallershouldrefertotrainingliterature
for further information in understanding fault messages.
13. If needed, make use of information provided below under
Troubleshooting:What to Expect with Normal Operation.
14.Independently confirm operation of any accessories
installedwiththeheatpumpsystem followinginstructions
provided with that equipment.
15.Complete the remainder of configuration settings and
entries as specified above under Installer Settings and
Other Configuration Entries.
16.For iQ Zone systems, confirm the zone system setup by
checking information on the ZONING DATA and ZONE
MODULESTATUSscreens,accessedfromtheSERVICE
INFORMATION menu.(See SYSTEM DIAGNOSIS AND
TROUBLESHOOTING below.).

16
SYSTEM DIAGNOSIS &TROUBLESHOOTING
Thefollowingisasummaryofnormalandabnormaloperation
fortypicalstartuptocheckoutthesystem. Referenceismade
to INSTALLER SETTINGS and SERVICE INFORMATION
screensdescribed above. Refertotrainingliterature formore
details.
Diagnostic information for the heat pump can be obtained
from all of the following sources:
• Controller displays. Refer to training materials for
interpretationoffaultmessages which appear ontheMain,
Fault Status, and Service Needed screens.
• Refrigerantsystempressureandtemperaturemeasurements
(using standard field service instrumentation)
• LED indicator lights on each of the system’s circuit boards
(see below).
Controller
Normal-Assoonas24vacpowerisapplied,thebluebacklight
of the controller should light up. The “iQ” splash screen will
display the software version. If the System Configuration
procedurehasnotbeenperformedyetforthissystem-controller
combination,“CONFIGURATION NEEDED”willbe displayed
across the top (alternating with other information).
IfthesystemhasaType“P”blowermotor(shownonSYSTEM
CONFIGURATIONandINDOORFANSTATUSscreens),used
inairhandlersorG6gasfurnaces,theblowerwillself-calibrate
for60secondsassoonasSystemConfigurationiscompleted.
All communications links in COMMUNICATION DATA
should show “OK”. All information displayed in the System
Configuration screen should be accurate.
Abnormal – If the display is not lit, check that 24 vac is being
providedbetweenthe“R”and“C”terminalsinthethermostat’s
back connection plate. If not, trace the connection of all
controllerwiresbacktotheindoorunit(furnaceorairhandler).
Check that connections are in accordance with field wiring
diagrams and instructions.
IfaSERVICENEEDEDscreenwitharedbacklightisdisplayed,
a fault has been detected. A brief description of the fault
is displayed on the screen. Access to the FAULT STATUS
screen is permitted.
If communication with the outdoor unit is OK but the unit
size (in tons) shown on the System Configuration screen in
wrong, contact the service representative of the equipment
distributor.Theinvertermaynothaveundergoneitsinitialization
procedure, performed at the factory.
Outdoor Unit Inverter
WARNING
ELECTRIC SHOCK HAZARD!
Disconnect power before servicing the
outdoor unit. Failure to follow these
instructions may result in electric shock or
death. Trouble-shooting the outdoor unit
may require that power be restored with
the control panel cover removed. Become
familiar with the control panel and hazardous
voltage areas before proceeding.
Time is required for inverter voltage to bleed
down after removal of line power.Wait at least
60 seconds after removing line voltage before
touching any inverter parts or wiring.
Normal – Examine the following with the control panel cover
off. Note the two smaller circuit boards mounted on a metal
“bridge” over the inverter.The red LED behind the upper right
side of the bridge should be lit and on steady when power is
applied to the inverter. Refer to Figures 3 and 12.
Abnormal –The red LED behind the upper right side of the
bridge is not lit. In this case, power is not being provided to
the inverter. Check that line voltage is being applied to the
bottom of the contactor. If so, check that 24 vac is being
provided across the contactor coil. If not, check the control
power wiring (RED and GRY wires) for 24 vac. Check that
the high pressure switch is closed. A fault indicating OD
UNIT COMM FAULT or OD UNIT LOST POWER would also
result from no line voltage applied.
The red LED behind the upper right side of the bridge is lit
but blinking. This indicates that the inverter is powered up
and that it detects a fault condition. If the controller does not
display a fault message, put the unit into HEAT or COOL
mode, and a message will be displayed. NOTE: When
line power is removed, the red LED will blink for about 1
minute before going out. Check that the 3- and 4-position
communication plugs are connected to the terminals marked
“INVERTER” and “INDOOR” on the right side of the outdoor
interface board.
Outdoor Unit Interface Board (right side small
circuit board)
Normal – Refer to Figure 13. The red LED at the upper left
of this board should do a “heartbeat” blink, consisting of a
double-blink followed by a pause, repeated. Note 4 other
LEDS towards the lower edge of the board. When the
compressor is off, the 3rd LED from the right should be
on (crankcase heater). When the compressor is running
in heating, the 2nd LED from the right should be on (EXV
enabled to open). When the unit is heating and in a defrost
cycle, the 1st and 4th LEDs from the right should be on.

17
When the compressor is running in cooling, the right-most
LED should be on (reversing valve is energized).
Abnormal – If no LEDs are lit on the board, 24 vac control
power is not being provided across the“R”and“C”terminals.
Check for this voltage between the left-most two screw
terminals (labeled R and C).
Outdoor Unit EXV Board (left side small circuit
board)
Normal – Refer to Figure 14.The green LED at the upper left
of this board should be steadily on, except that a blink at a
regular rate can be expected during cooling operation.
Abnormal – If the green LED is not lit, the EXV board is not
getting24vacpowerfromtheinterfaceboardnexttoit. Check
for24 vacbetweenRand Contheinterfaceboard,andcheck
that the tabs marked “R” and “C” on the interface board are
wired to “R” and “C” on the EXV board (red and gray wires,
respectively). These should not be cross-wired.
If the green LED is blinking at a regular rate during heat
pump heating, it indicates that one of the two EXV sensors
is reading out of range. Refer to training literature for sensor
interpretation and troubleshooting.
IfthegreenLEDisblinkingatanon-uniformrate(heartbeat),it
indicatesthat theboard hasbeen placedin theManualMode.
Hold down the small black button on the board for more than
3 seconds to return it to automatic control mode.
Indoor Unit Interface Board
(in G6 iQ furnace kit or air handler)
Normal – The red LED at the upper left of this board should
do a “heartbeat” blink, consisting of a double-blink followed
by a pause, repeated. Note 4 other LEDS towards the lower
edge of the board. When the equipment is off, none of the
LEDs should be on. If the furnace or electric strip heat is
on, 3rd LED or 3rd and 4th LEDs from the right should be
on (first and second stage auxiliary heat). When the unit is
cooling the right-most LED should be on (EXV enabled to
open). If humidification is called for, the 2nd LED from the
right should be on.
Abnormal – If no LEDs are lit on the board, 24 vac control
power is not being provided across the“R”and“C”terminals.
Check for this voltage between the left-most two screw
terminals (labeled R and C).
Indoor Unit EXV Board
Normal – The green LED at the upper left of this board
should be steadily on, except that a blink at a regular rate
can be expected during heat pump heating operation.
Abnormal – If the green LED is not lit, the EXV board is not
getting 24 vac power from the interface board. Check for
24 vac between R and C on the interface board, and check
that the tabs marked “R” and “C” on the interface board are
wired to “R” and “C” on the EXV board.These should not be
cross-wired.
If the green LED is blinking at a regular rate during cooling,
it indicates that one of the two EXV sensors is reading out
of range. Refer to training literature for sensor interpretation
and troubleshooting.
IfthegreenLEDisblinkingatanon-uniformrate(heartbeat),it
indicatesthat theboard hasbeen placedin theManualMode.
Hold down the small black button on the board for more than
3 seconds to return it to automatic control mode.
Indoor Unit Constant CFM Motor Control Board
Normal – The red LED near the top of the board should be
on steadily. The green LED near the top of the board should
have a“heartbeat”blink, consisting of a double-blink followed
by a pause, repeated. Of the four LEDs towards the left side
of the board, the lowest one marked “H” should be on when
humidification is called for.
Abnormal – If the green LED near the top of the board is not
lit, the board is not connected to the communication network
properly. If the red LED near the top of the board is not lit, the
boardisnotgetting24vaccontrolpowerfromthefurnaceboard.
IndoorUnitOne-orTwo-StageG7FurnaceBoard
Normal – The red and green LEDs should be on steadily.
When the furnace is on and a flame is detected, the amber
LED should be on.
Abnormal – The LEDs will provide a diagnostic code through
their blink pattern. Refer to furnace Installation Instructions
for detailed troubleshooting.
Indoor Unit iQ Modulating Gas Furnace Board
Normal – The red LED should be on steadily. The green LED
near the top of the board should have a “heartbeat” blink,
consisting of a double-blink followed by a pause, repeated.
When the furnace is on and a flame is detected, the amber
LED should be on.
Abnormal – The LEDs will provide a diagnostic code through
theirblinkpattern. RefertofurnaceInstallationInstructionsfor
detailed troubleshooting. If the green LED alone is not lit, the
boardisnotconnectedtothecommunicationnetworkproperly.
Airzone Control Board
Normal – One red power LED should be on steady near
where the dc power plugs into the board (upper left corner).
Red and green LEDs at the lower right side of the board (just
below the DIP switch block) flash quickly and continuously
(indicating zone network activity). A second set of red and
green LEDs (about 1” to the left of the other green and red
LED pair) also flash, with the red LED flashing every 3 to 5
seconds, indicating iQ bus communication. See Figure 15.

18
CommonTroubleshooting Issues
Compressor Does Not Start Immediately
• Fornormaloperationwithoutchangingmodesofoperation,
thecompressorwillnotrestartuntil5minutes(theminimum
off time) have expired since it shut off last.
• A minimum demand of 0.5°F is required before the heat
pump (heating or cooling) will start up.
• The system will wait 5 minutes following detection of a fault
condition before attempting a restart.
Compressor Does Not Shut Off Immediately
• Fornormaloperationwithoutchangingmodesofoperation,
thecompressorwillnotshutoffuntil5minutes(theminimum
run time) have expired since it started last.
The Outdoor Fan Does Not Shut Off When the
Compressor Does
• For normal operation the outdoor fan is designed to run for
30 seconds after the compressor shuts off.
In Cooling, the Blower Slows Down and the Unit
Is Not Responding to Room Temperature
• Slowingofblowerspeedandsuspensionofnormalcapacity
control will occur when the unit goes into Dehumidification.
If conditions for dehumidification persist, the unit will run
cyclesof10minutesindehumidification,5minutesinnormal
cooling (responding to room temperature).
In Heating, the Unit Appears to be Cooling
• During heat pump heating when the outdoor temperature
is in the mid-30’s (°F) or lower, the unit will periodically
go into a Demand Defrost operation. After power to the
controller is turned on, the first defrost may occur as soon
as 34 minutes after startup. Subsequently, defrost will be
determinedbyoutdoorcoiltemperatureorbythemaximum
time between defrosts of 6 hours (if the coil temperature is
low enough).
In Heat Pump Heating, the Furnace Runs At the
Same Time
• The indoor (backup) heating system will operate during
defrost cycles. (See above item.)
In Heating, the Furnace or Electric Heat Runs
Instead of the Heat Pump
• The indoor backup heat equipment will run instead of the
heat pump if (a) the outdoor air temperature is below the
Minimum Heat Pump Usage Limit, (b) the heat pump is in
a fault condition, or (c) the heat pump is not able to satisfy
the demand (after a time delay).
The System Is In AUTO Mode, but It Won’t Switch
Quickly From Heating to Cooling (or the Reverse)
• There is a configurable delay (Auto Changeover Time)
between operating in heating and restarting in cooling (or
the reverse) when in AUTO mode. The default delay for
this changeover is 60 minutes.
Abnormal – If the red LED near the dc power plug is not on,
thentheAC/DCpowersupplyisnot connectedornotworking.
If the red LED 1 ½” from the lower right edge does not flash,
the module is not communicating properly on the iQ bus.
iQ Zone System Configuration
Normal–ChecktheZONINGDATAscreenfromtheSERVICE
INFORMATION menu (shown on page 11). In the lower
portion of the screen the zone weights shown should match
the intended values, and they should add up to 100(%).
ZONE MODULE STATUS
PREVIOUS
MOD
1Z10
2Z20
3Z3X
4Z40
5Z50
6Z
7Z
8Z
9Z10
10Z12
MOD
11Z10
12Z10
13Z20
14Z23
15Z20
16Z20
17Z3X
18Z3X
19Z42
20Z40
MOD
21Z50
22Z
23Z
24Z
25Z
26Z
27Z
28Z
29Z
30Z
31Z20
32Z
Press the key to view the ZONE MODULE STATUS screen
(shownhere).Everymoduleinstalledinthesystemshouldshow
up on this list with the proper zone identification number after
the“Z”, followed by a“0”. For example,“23Z40”is module 23
inzone4.The“0”indicatesnormalfunctioning.Zonenumbers
shouldonlyappearwithmodulenumbersthatwereintendedto
be assigned.For master zone modules 1-8, the zone number
must match the module number.
Abnormal – If any zone weight shown in the ZONING DATA
screen is incorrect, or if the total for the eight zones is not
100(%), make the appropriate corrections from the zone
thermostat for the zone(s) which require(s) correction.
If an installed zone module does not show up in the ZONE
MODULE STATUS screen with an assigned zone number,
such as with module 25 in the figure, check the wiring to that
zone module. If the zone number is wrong or if the wrong
module number shows up as used, the module needs to be
reconfigured. If the last character after the zone number is
not “0”, look for the following problems:
• “1” may indicate a disconnected damper motor connector.
• “2” may indicate a damper that is jammed due to blockage
from a foreign object or damage or dirt on the internal
transmission.
• “3” may indicate that a zone thermostat is not connected
properly to its associated master zone module (1-8).
• “X” may indicate that a module is assigned but not
communicating.

19
Figure 2. Power Wiring ConnectionsFigure 1. Unit Envelope Dimensions
18"
CONTROL
PANEL
EXTERIOR WALL
18"
18"
18"
FIGURES & DIAGRAMS
Although There Is a Large Demand At Startup,
the Compressor Only Runs at Medium Speed
• Regardlessofdemandthesystemwillalwaysstart and run
atan intermediatespeedforoneminute. Subsequentlythe
speed may increase significantly.
Humidification or Dehumidification Setpoints Are
Not Being Satisfied
• Thefirst priorityofthesystemistoachievethetemperature
setpoint(s). While under most circumstances it will also
satisfy humidity setpoints, its ability to accomplish this is
significantlyaffectedbyavarietyofinstallation-basedfactors
and circumstances.
In an iQ Zone System, the system does not
respond promptly to changes in setpoint or mode
• With zoning systems additional delays may be noticed.
Most commonly this is due to no new changes processed
until zone dampers have completed any prior operation.
For example, an extra minute delay is deliberately included
when one or more zones are closed.
MAINTENANCE
IMPORTANT:
Be certain the electrical power to the outdoor unit
andthefurnaceorairhandlerisdisconnectedbefore
doing the following recommended maintenance.
• Inspect the indoor air filter monthly. Clean or replace it at
the start of each heating and cooling season or when an
accumulationofdustordirtisvisible. Iftheindoorcoilneeds
to be cleaned, contact a qualified service technician.
• Inspectthe condensate disposal linefromthe indoor coil at
the beginning of the cooling season to make sure it is not
obstructed.
• Remove any leaves, grass clippings, and debris from the
outdoorunitcoil,beingcarefulnottodamagethealuminum
fins.Dirtmaybeclearedfrom thecoilbyusinga waterhose
directedthrough the discharge fangrilletowardthe outside
of the unit.
• Have a yearly inspection by a qualified service technician
to ensure that the system is performing at its optimal level.

20
Figure 3. iQ Drive Heat Pump Control Panel
Inverter
(black plastic case)
Outdoor
Interface Board
LowVoltage
ControlWiring
Compartment
Contactor
Outdoor
EXV Board
}
}
}
}