Nordyne R-410A User manual

Outdoor Heat Pump
Two Stage R-410A Split System
User’s Information/Installation Instructions
These units have been designed and tested for capacity and efficiency in accordance with A.R.I.
Standards. Split System Heat Pump units are designed for use with a wide variety of fossil fuel
furnaces, electric furnaces, air handlers, and evaporator coil combinations equipped with variable
speed in blowers.
These instructions are primarily intended to assist qualified individuals experienced in the proper
installation of heating and/or air conditioning appliances. Some local codes require licensed instal-
lation/service personnel for this type of equipment. Read all instructions carefully before starting
the installation.
IMPORTANT
Read this owner information to become familiar with the capabilities and use of your appliance.
Keep this with literature on other appliances where you have easy access to it in the future. If a
problem occurs, check the instructions and follow recommendations given. If these suggestions
don’t eliminate your problem, call your servicing contractor. NOTE: For this type of equipment to
function as intended for maximum efficiency and adequate capacity, a two stage cooling/heating
thermostat is required. See unit wiring diagram.
Heat Pump Principle of Operation
USER’S INFORMATION
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SUMMER COOLING
1. Indoor air enters the air handler section.
2. Cold, heat-transfer section (indoor coil)
extracts heat from indoor air as refrigerant
evaporates from a liquid to a cold gas.
3. Refrigerant, drawn to heat pump and
compressed to a hot gas by heat pump,
carries the heat outdoors.
4. Hot, heat-transfer section (outdoor coil)
releases the heat as refrigerant condenses
from a gas to a liquid.
5. Heat pump (outdoor fan) discharges the
heat to outside air.
6. Refrigerant returns to indoor coil and
evaporates once again to absorb more
heat.
WINTER HEATING
1. Outdoor air enters heat pump.
2. Cold, heat-transfer section (outdoor coil)
extracts heat from outdoor air as refrigerant
evaporates from a liquid to a gas.
3. Refrigerant, compressed to a hot gas by
heat pump, carries the heat to the hot heat-
transfer section (indoor coil).
4. Hot, heat-transfer section (indoor coil)
releases the heat to indoor air as refrigerant
condenses from a gas to a liquid.
5. Air handler circulates the heat throughout
the home.
6. Refrigerant returns to outdoor coil and
evaporates once again to absorb more
heat.

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Figure 1. Typical Thermostat
OPERATING INSTRUCTIONS
TO OPERATE YOUR HEAT PUMP
FOR COOLING —
1. Set the thermostat system switch to COOL
and the thermostat fan switch to AUTO.(See
Figure 1)
2. Set the thermostat temperature to the
desired temperature level using the tem-
perature selector. Please refer to the sepa-
rate detailed thermostat user’s manual for
complete instructions regarding thermostat
programming.The outdoor unit and indoor
blower will both cycle on and off to maintain
the indoor temperature at the desired cool-
ing level.
NOTE: If the thermostat temperature level
is re-adjusted, or the thermostat system
switch is repositioned, the outdoor unit
may not start immediately.The outdoor unit
contains a protective timer circuit which
holds the unit off for approximately three
minutes following a previous operation,
or the interruption of the main electrical
power.
TO OPERATE YOUR HEAT PUMP
FOR HEATING —
1. Set the thermostat system switch to HEAT
and the thermostat fan switch to AUTO.
(See Figure 1)
2. Set the thermostat temperature to the
desired temperature level using the
temperature selector. Please refer to
the separate detailed thermostat user’s
manual for complete instructions regarding
thermostat programming.The outdoor unit
and indoor blower will both cycle on and off
to maintain the indoor temperature at the
desired heating level.
NOTE: If the thermostat temperature level
is re-adjusted, or the thermostat system
switch is repositioned, the outdoor unit
may not start immediately.The outdoor unit
contains a protective timer circuit which
holds the unit off for approximately three
minutes following a previous operation,
or the interruption of the main electrical
power.
Emergency Heat:
The thermostat includes a system switch
position termed EM. HT. This is a back-up
heating mode to be used only if there is
a suspected problem with the outdoor
unit. With the system switch set to EM.
HT. the outdoor unit will be locked off,
and supplemental heat (typically electric
resistance heating) will be used as a source
of heat.Sustained use of electric resistance
heat in place of the heat pump will result in
an increase in electric utility costs.
Defrost:
During cold weather heating operation, the
outdoor unit will develop a coating of snow

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The continuous indoor blower operation can be
obtained with the thermostat system switch set
in any position, including OFF.
The continuous indoor blower operation is
typically used to circulate the indoor air to
equalize a temperature unbalance due to a sun
load, cooking, or fireplace operation.
TO MAINTAIN YOUR HEAT PUMP —
CAUTION:
Be certain the electrical power to
the outdoor unit and the furnace/air
handler is disconnected before
doing the following recommended
maintenance.
1. Regularly:
a. Clean or replace the indoor air filter at the
start of each heating and cooling season,
and when an accumulation of dust and dirt
is visible on the air filter. Inspect the filter
monthly.
b. Remove any leaves and grass clippings from
the coil in the outdoor unit, being careful
not to damage the aluminum fins.
c. Check for any obstruction such as twigs,
sticks, etc.
CAUTION:
Do not over-oil, or oil motors not
factory-equipped with oil tubes. The
compressor is hermetically “sealed”
and does not require lubrication.
2. Before Calling a Service Technician, Be
Certain:
a. The unit thermostat is properly set, see
“To OperateYour Heat Pump for Cooling”
and “To Operate Your Heat Pump for
Heating.”
b. The unit disconnect fuses are in good
condition, and the electrical power to the
unit is turned on.
and ice on the heat transfer coil. This is
normal, and the unit will periodically defrost
itself.These units employ Adaptive Demand
Defrost Feature that monitors ambient and
coil temperatures and regulate defrost
function accordingly. At the beginning of the
defrost cycle, both the outdoor condenser
fan and compressor will de-energize. After
approximately 30 seconds, the compressor
will energize and begin to heat the outdoor
coil causing the ice and snow to melt.
After the ice and snow have melted, some
steam may rise from the outdoor unit as
the warm coil causes some melted frost
to evaporate. Once the defrost cycle is
completed, the outdoor fan motor will start,
and the compressor will de-energize again
for approximately 30 seconds. Then, the
compressor will energize and continue
normal operation.
TO OPERATE YOUR HEAT PUMP
FOR AUTOMATIC COOLING AND
HEATING —
1. Set the thermostat system switch to AUTO
and the thermostat fan switch to AUTO.(See
Figure 1)
Note: Thermostats will vary. Some models
will not include the AUTO mode, and others
will have the AUTO in place of the HEAT and
COOL, and some will include all three.
2. Set the thermostat temperature to the
desired heating and cooling temperature
level(s). The outdoor unit and the indoor
blower will then cycle on and off in either
the heating or cooling mode of operation
as required to automatically maintain the
indoor temperature within the desired
limits.
TO SHUT OFF YOUR HEAT PUMP —
Set the thermostat system switch to OFF and
the thermostat fan switch to AUTO. (See Figure
1) The system will not operate, regardless of the
thermostat temperature selector(s) setting.
TO OPERATE THE INDOOR
BLOWER CONTINUOUSLY —
Set the thermostat fan switch to ON (See
Figure 1). The indoor blower will start and will
run continually until the fan switch is reset to
AUTO.

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Read Your Warranty
Please read the separate warranty document
completely. It contains valuable information
about your system.
GENERAL INFORMATION
CAUTION:
This unit uses R-410A. DO NOT under
any circumstance use any other
refrigerant besides R-410A in this unit.
Use of another refrigerant will damage
this unit.
Read the following instructions completely before
performing the installation.
Outdoor Unit Section — Each outdoor unit
is shipped with a refrigerant charge adequate
to operate the outdoor section with an indoor
matching coil or air handler. These units include
the proper amount of refrigerant for an additional
15 ft. of refrigerant lines the same size as the
valve fittings.
NOTE: DO NOT USE ANY PORTION OF
THE CHARGE FOR PURGING OR LEAK
TESTING.
Matching coils and air handlers may be shipped
with a small holding charge to pressurize them to
keep out contaminants.To release the pressure,
read the indoor section installation instructions
carefully.
Liquid and Suction Lines — Fully annealed,
refrigerant grade copper tubing should be used
when installing the system. Refrigerant suction
line tubing should be fully insulated.
Field Connections for Electrical Power
Supply — All wiring must comply with current
provisions of the “National Electrical Code”
(ANSI/NFPA 70) and with applicable local
codes having jurisdiction. The minimum size of
electrical conductors and circuit protection must
be in compliance with information listed on the
outdoor unit data label.
SAFETY CONSIDERATIONS
Pressures within the System — Split
system heat pump equipment contains liquid
and gaseous refrigerant under pressure.
Installation and servicing of this equipment
should be accomplished by qualified, trained
personnel thoroughly familiar with this type of
equipment. Under no circumstances should the
Homeowner attempt to install and/or service
the equipment.
Labels, Tags, Precautions — When working
with this equipment, follow all precautions in the
literature, on tags, and on labels provided with
the equipment.Read and thoroughly understand
the instructions provided with the equipment prior
to performing the installation and operational
checkout of the equipment.
Brazing Operations — Installation of equipment
may require brazing operations. Safety codes
must be complied with. Safety equipment (e.g.;
safety glasses, work gloves, fire extinguisher,
etc.) must be used when performing brazing
operations.
WARNING:
Ensure all electrical power to the unit
is off prior to installing or servicing
the equipment. Failure to do so may
cause personal injury or death.
SITE PREPARATION
Unpacking Equipment — Remove the
cardboard carton and User’s Manual from the
equipment. Take care to not damage tubing
connections when removing from the carton.
Inspect for Damage — Inspect the equipment
for damage prior to installing the equipment at
the job site. Ensure coil fins are straight and, if
necessary, comb fins to remove flattened and
bent fins.
Preferred Location of the Outdoor Unit at the
Job Site — Conduct a survey of the job site to
determine the optimum location for mounting
the outdoor unit. Overhead obstructions,
poorly ventilated areas, and areas subject to
accumulation of debris should be avoided. The
outdoor unit should be installed no closer than
18 inches from the outside walls of the facility
and in an area free from overhead obstructions
to ensure unrestricted airflow through the
outdoor unit.
Facility Prerequisites — Electrical power
supplied must be adequate for proper operation

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during system operation. Tubing should be kept
clean of foreign debris during installation. Every
effort should be made by the installer to ensure
that the field installed, refrigerant containing
components of the system have been installed
in accordance with these instructions and sound
installation practices so as to insure reliable
system operation and longevity.
The maximum recommended interconnecting
refrigerant line length is 75 feet, and the
vertical elevation difference between the indoor
and outdoor sections should not exceed 20
feet. Consult long line application guide for
installations in excess of these limits.
Filter Dryer Installation — A filter dryer is
provided with the unit and must be installed in the
liquid line of the system.If the installation replaces
a system with a filter dryer already present in the
liquid line, the filter dryer must be replaced with
the one supplied with the unit. The filter dryer
must be installed in strict accordance with the
manufacturer’s installation instructions.
Optional Equipment — Optional equipment
(e.g.:low ambient control, etc.) should be installed
in strict accordance with the manufacturer’s
installation instructions.
ELECTRICAL CONNECTIONS
WARNING:
Turn off all electrical power at the main
circuit box before wiring electrical
power to the outdoor unit. Failure to
comply may cause severe personnel
injury or death.
Wiring Diagram/Schematic — A wiring
diagram/schematic is located on the inside cover
of the electrical box of the outdoor unit. The
installer should become familiar with the wiring
diagram/schematic before making any electrical
connections to the outdoor unit.
Outdoor Unit Connections — The outdoor unit
requires both power and control circuit electrical
connections. Refer to the unit wiring diagram/
schematic for identification and location of
outdoor unit field wiring interfaces.
Control Circuit Wiring — The outdoor unit is
designed to operate from a 24 VAC Class II
control circuit. Control circuit wiring must comply
with the current provisions of the “National
of the equipment.The system must be wired and
provided with circuit protection in accordance
with local building codes and the National
Electrical Code.
INSTALLING THE OUTDOOR UNIT
Slab Mount —The site selected for a slab mount
installation requires a stable foundation and one
not subject to erosion. The slab should be level
and anchored (if necessary) prior to placing the
equipment on the slab.
Cantilever Mount — The cantilever mount
should be designed with adequate safety factor
to support the weight of the equipment, and for
loads subjected to the mount during operation.
Installed equipment should be adequately
secured to the cantilever mount and levelled
prior to operation of the equipment.
Roof Mount — The method of mounting should
be designed so as not to overload roof structures
nor transmit noise to the interior of the structure.
Refrigerant and electrical line should be routed
through suitably waterproofed openings to
prevent water leaking into the structure.
INSTALLING THE INDOOR UNIT
The indoor section should be installed before
proceeding with routing of refrigerant piping.
Consult the Installation Instructions of the indoor
unit (i.e.: air handler, furnace, etc.) for details
regarding installation.
CONNECTING REFRIGERANT
TUBING BETWEEN THE INDOOR
AND OUTDOOR UNIT
CAUTION:
This system utilizes R-410A refrigerant
with POE oil. When servicing, cover
or seal openings to minimize the
exposure of the refrigerant system
to air to prevent accumulation of
moisture and other contaminants.
General — Once outdoor and indoor unit
placement hasbeen determined, route refrigerant
tubing between the equipment in accordance with
sound installation practices. Refrigerant tubing
should be routed in a manner that minimizes the
length of tubing and the number of bends in the
tubing.Refrigerant tubing should be supported in
a manner that the tubing will not vibrate or abrade

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Electrical Code” (ANSI/NFPA 70) and with
applicable local codes having jurisdiction.
Thermostat connections should be made in
accordance with the instructions supplied with
the thermostat, and with the instructions supplied
with the indoor equipment. A typical residential
installation with a heat pump thermostat and air
handler are shown below.
Electrical Power Wiring — Electrical power
wiring must comply with the current provisions
of the “National Electrical Code” (ANSI/NFPA
70) and with applicable local codes having
jurisdiction. Use of rain tight conduit is
recommended. Electrical conductors shall have
minimum circuit ampacity in compliance with the
outdoor unit rating label. The facility shall employ
electrical circuit protection at a current rating no
greater than that indicated on the outdoor unit
rating label. Refer to the unit wiring diagram for
connection details.
Minimum Circuit Ampacity — Electrical wiring
to the equipment must be compatible and in
compliance with the minimum circuit ampacity
listed on the outdoor unit data label.
Maximum Fuse/Circuit Breaker Size —
Circuit protection for the outdoor unit must
be compatible with the maximum fuse/circuit
breaker size listed on the outdoor unit data
label.
Disconnect Switch — An electrically compatible
disconnect switch must be within line of sight of
the outdoor unit. This switch shall be capable of
electrically de-energizing the outdoor unit.
Optional Equipment — Optional equipment
requiring connection to the power or control
circuits must be wired in strict accordance with
current provisions of the National Electrical
Code (ANSI/NFPA 70), with applicable local
codes having jurisdiction, and the installation
instructions provided with the equipment.
Optional Equipment (e.g.: low ambient control,
hard start kits, etc.) should be installed in strict
accordance with the manufacturer’s installation
instructions.
STARTUP AND CHECKOUT
WARNING:
Ensure electrical power to the unit is
off prior to performing the following
steps. Failure to do so may cause
personal injury or death.
Air Filters — Ensure air filters are clean and in
place prior to operating the equipment.
Thermostat — Set the room thermostat function
switch to OFF, fan switch to AUTO, and adjust the
temperature setpoint to its highest setting.
Prior to applying electrical power to the outdoor
unit, ensure that the unit has been properly and
securely grounded, and that power supply
connections have been made at both the facility
power interface and outdoor unit.
Outdoor Unit — Ensure the outdoor coil and
top of the unit are free from obstructions and
debris, and all equipment access/control panels
are in place.
Using extreme caution, apply power to the unit
and inspect the wiring for evidence of open,
shorted, and/or improperly wired circuits.
Functional Checkout:
CAUTION:
These units have a crankcase heater
factory installed. Wait 24 hours prior
to performing a function checkout to allow
for heating of the compressor crankcase.
Failure to comply may result in damage
and could cause premature failure of the
system.
Indoor Blower — Turn the fan switch to ON.
Verify that the indoor blower is operating and
that airflow is not restricted. Set the fan switch
Wire Size based on N.E.C. for 60° type copper
conductors.
COPPER WIRE SIZE — AWG
(1% Voltage Drop)
Supply Wire Length-Feet Supply Circuit
Ampacity
200 150 100 50
6 8 10 14 15
46812 20
46810 25
44610 30
3 468 35
3 468 40
2 346 45
2 346 50
2 346 55
1 234 60

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Typical 2-Stage Heat Pump System Connection
G R W2 C E O Y1
Thermostat
OD
Stat
OY1
R
C
Air Handler Heat Pump OD Section
W2
E
Typical 2-Stage Cooling Heat Pump with
Optional Outdoor Thermostat and Variable
Speed Air Handler
W2
W1
O
Y/Y2
G
R
C
Y2
Y2
W1 W3
Y1
NOTE: Jumper
W1 and W2
together for
shorter
staging time.
See table 2

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back to AUTO.Blower will operate at a decreased
speed on continuous fan.
2-Speed Outdoor Fan Motor (Select
Models) — If unit utilizes a 2-speed condenser
fan motor, this motor will operate on low speed
when in low cooling, and on high speed when
in high cooling. A relay within the control area
switches the fan motor from low to high speed
using the call for high cooling as the trigger.
Low-Pressure Switch — A low-pressure switch
is factory-installed and located in the suction
line internal to the outdoor unit. The switch is
designed to protect the compressor from a loss
of charge. Under normal conditions, the switch
is closed. If the suction pressure falls below 5
psig, then the switch will open and de-energize
the outdoor unit. The switch will close again
once the suction pressure increases above 20
psig. Please note that the switch interrupts the
thermostat inputs to the unit. Thus, when the
switch opens and then closes, there will be a 5
minute short cycling delay before the outdoor
unit will energize.
High-Pressure Switch — A high-pressure switch
is factory-installed and located in the compressor
discharge line internal to the outdoor unit. The
switch is designed to de-energize the system
when very high pressures occur during abnormal
conditions.Under normal conditions, the switch is
closed.If the discharge pressure rises above 650
psig, then the switch will open and de-energize
the outdoor unit. The switch will close again
once the discharge pressure decreases to 460
psig. Please note that the switch interrupts the
thermostat inputs to the unit. Thus, when the
switch opens and then closes, there will be a 3
minute short cycling delay before the outdoor
unit will energize.
Short Cycle Protection — With the system
operating in COOLING mode, note the setpoint
temperature setting of the thermostat, and
gradually raise the setpoint temperature until
the outdoor unit and indoor blower de-energize.
Immediately lower the setpoint temperature of
the thermostat to its original setting and verify
that the indoor blower is energized and that the
outdoor unit remains de-energized. Verify that,
after approximately 3 minutes, the outdoor unit
energizes and that the temperature of the air
supplied to the facility is cooler than ambient
temperature.
Comfort AlertTM Diagnostics — The Comfort
AlertTM diagnostics module is a breakthrough
innovation for troubleshooting heat pump and
air conditioning system failures. The module
installs easily in the electrical box of the
outdoor unit near the compressor contactor.
By monitoring and analyzing data from the
Copeland scroll compressor and the thermostat
demand, the module can accurately detect the
cause of electrical and system related failures
without any sensors. A flashing LED indicator
communicates the ALERT code and guides the
service technician more quickly and accurately
to the root cause of a problem.
NOTE: This module does not provide safety
protection! The Comfort AlertTM module is a
monitoring device and cannot control or shut
down other devices.
LED Description (See Figure 1)
POWER LED (Green): indicates voltage
is present at the power connection of the
module.
ALERT LED (Yellow): communicates an
abnormal system condition through a unique
flash code.The ALERT LED will flash a number
of times consecutively, pause and then repeat
the process. The number of consecutive
flashes, defined as the Flash Code, correlates
to a particular abnormal condition. Detailed
descriptions of specific ALERT Flash Codes are
shown in Table 1 of this manual.
TRIP LED (Red): indicates there is a demand
signal from the thermostat but no current to the
compressor is detected by the module.TheTRIP
LED typically indicates the compressor protector
is open or may indicate missing supply power
to the compressor.
The scroll compressor’s run (R), common (C) and
start (S) wires are routed through the holes in
the Comfort AlertTM module marked “R,” “C” and
“S.”The common (C) need not be routed through
the module for it to operate properly.
24 VAC Power Wiring — The Comfort AlertTM
module requires a constant nominal 24 VAC
power supply. The wiring to the module’s R and
C terminals must be directly from the indoor unit
or thermostat.The module cannot be powered by
the C terminal on a defrost board or other control
board without experiencing nuisance alerts.

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When constant 24 VAC (R) wire) is not present
in the outdoor unit, use one of the spare wires
in the thermostat cable to bring power to the
module.Connect the other end of the spare wire
to R at the indoor unit or thermostat.
Thermostat Demand Wiring — The Comfort
AlertTM module requires a thermostat demand
signal to operate properly. The thermostat
demand signal input, labeled Y on the module,
should always be connected to the compressor
contactor coil so that when the coil is energized,
the demand signal input is 24 VAC when the coil
is not energized, the demand signal input should
be less than 0.5 VAC.
NOTE: Factory installed modules have differ-
ent thermostat demand signal wiring. Follow
manufacturer’s wiring instructions when replac-
ing module.
NOTE: After the thermostat demand signal is
connected, verify that 24 VAC across Y and C
when demand is present.
Cooling — Gradually lower the thermostat
temperature setpoint below the actual room
temperature and observe that the outdoor unit
and indoor blower energize. Feel the air being
circulated by the indoor blower and verify that
it is cooler than ambient temperature. Listen
for any unusual noises. If present, locate and
determine the source of the noise and correct
as necessary.
Heating — If provided with heating equipment,
lower the thermostat setpoint temperature to the
lowest obtainable setting and set the thermostat
function switch to HEATING. The outdoor unit
should stop running. The indoor blower will go
off after the preprogrammed delay. Increase
the setpoint temperature of the thermostat to
the maximum setting. Verify that the heating
equipment has been energized (i.e., fossil fuel
burner operating, etc.) and that the indoor blower
energizes after a short period of time. Feel the
air being circulated by the indoor blower and
verify that it is warmer than ambient temperature.
Listen for any unusual noises. If present, locate
and determine the source of the noise and cor-
rect as necessary.
NOTE: Other sources for heating (i.e.: electric
furnace, fossil fuel furnace, air handler with
electric heat options, etc.) that interface with
the heat pump should be functionally checked
to verify system operation and compatibility with
the heat pump. Refer to the installation instruc-
tions for this equipment and perform a functional
checkout in accordance with the manufacturer’s
instructions.
Optional Equipment — A functional checkout
should be performed in accordance with the
checkout procedures supplied with the equip-
ment.
Defrost Cycle Control — The Adaptive Demand
defrost controls the defrost cycle in response
to adaptive demand algorithm that uses coil
Figure 2. Comfort AlertTM Diagnostics
Module
POWER
ALERT
TRIP

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Table 1. Interpreting the Diagnostic LEDS
Status LED Status LED Description Status LED Troubleshooting Information
Green “POWER” Module has power Supply voltage is present at module terminals
Red “TRIP” Thermostat demand signal 1. Compressor protector is open
• Check for high head pressure
• Check compressor supply voltage
Y is present, but the
compressor is not
running 2. Outdoor unit power disconnect is open
3. Compressor circuit breaker or fuse(s) is open
4. Broken wire or connector is not making contact
5. Low pressure switch open if present in system
6. Compressor contactor has failed open
Yellow “ALERT” Long Run Time 1. Low refrigerant charge
Flash Code 1 Compressor is 2. Evaporator blower is not running
• Check blower relay coil and contacts
• Check blower motor capacitor
• Check blower motor for failure or blockage
• Check evaporator blower wiring and connectors
• Check indoor blower control board
• Check thermostat wiring for open circuit
running extremely
3. Evaporator coil is frozen
• Check for low suction pressure
• Check for excessively low thermostat setting
• Check evaporator airflow (coil blockages or return airfilter)
• Check ductwork or registers for blockage
long run cycles
4. Faulty metering device
• Check TXV bulb installation (size, location and contact)
• Check if TXV/fixed orifice is stuck closed or defective
5. Condenser coil is dirty
6. Liquid line restriction (filter drier blocked if present in system)
7. Thermostat is malfunctioning
• Solenoid plug not connected
• Y2 not wired at Comfort Alert
8. Thermostat is malfunctioning
• Check thermostat sub-base or wiring for short circuit
• Check thermostat installation (location, level)
9. Comfort Alert failure
Yellow “ALERT” System Pressure Trip 1. High head pressure
• Check high pressure switch if present in system
• Check if system is overcharged with refrigerant
• Check for non-condensable in system
Flash Code 2 Discharge or suction
2. Condenser coil poor air circulation (dirty, blocked, damaged)
pressure out of limits
or
3. Condenser fan is not running
• Check fan capacitor
• Check fan wiring and connectors
• Check fan motor for failure or blockage
compressor overloaded
4. Return air duct has substantial leakage
5. If low pressure switch present in system, check Flash
Code 1 information
Yellow “ALERT” Short Cycling 1. Thermostat demand signal is intermittent
Flash Code 3 Compressor is running 2. Time delay relay or control board defective
only briefly 3. If high pressure switch present go to Flash Code 2 information
4. If low pressure switch present go to Flash Code 1 information
Yellow “ALERT” Locked Rotor 1. Run capacitor has failed
Flash Code 4 2. Low line voltage (contact utility if voltage at disconnect is low)
• Check wiring connections
3. Excessive liquid refrigerant in compressor
4. Compressor bearings are seized
• Measure compressor oil level

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temperature and ambient temperature.It provides
user selectable defrost termination temperature
(50 °F - 80 °F coil temperature).
Control is uncalibrated when power is applied.
Calibration occurs after a defrost cycle. The
control initiates this sacrificial defrost after 34
minutes of accumulated compressor run time
in heating with coil temperature below 35 °F.
The cycle terminates if coil sensor reaches
selected termination temperature or after 14
minutes defrost.
Defrost function is disabled if coil temperature
is above 35 °F. If Ambient sensor is detected as
open or shorted, demand defrost will not operate
and control will revert to time/temperature defrost
operation. If the outdoor coil sensor is detected
as open or shorted, the control will not perform
demand or time/temperature defrost operation.
Please note that when the defrost cycle initiates,
there will be a 30 second compressor delay
going into and out of the defrost cycle.This delay
may be removed by removing P6 connector on
the board.
This 2-stage unit will defrost in second stage
regardless of the stage called for by the
thermostat.
Table 1. Interpreting the Diagnostic LEDS (Cont.)
Yellow “ALERT” Open Circuit 1. Outdoor unit power disconnect is open
Flash Code 5 2. Compressor circuit breaker or fuse(s) is open
3. Compressor contactor has failed open
• Check compressor contactor wiring and connectors
• Check for compressor contactor failure (burned, pitted or
open)
• Check wiring and connectors between supply and
compressor
• Check for low pilot voltage at compressor contactor coil
4. High pressure switch is open and requires manual reset
5. Open circuit in compressor supply wiring or connections
6. Unusually long compressor protector reset time due to
extreme ambient temperature
7. Compressor windings are damaged
• Check compressor motor winding resistance
Yellow “ALERT” Open Start Circuit 1. Run capacitor has failed
Flash Code 6 Current only in run circuit 2. Open circuit in compressor start wiring or connections
• Check wiring and connectors between supply and the
compressor “S” terminal
3. Compressor start winding is damaged
• Check compressor motor winding resistance
Yellow “ALERT” Open Run Circuit 1. Open circuit in compressor run wiring or connections
Flash Code 7 Current only in start circuit • Check wiring and connectors between supply and the
compressor “R” terminal
2. Compressor run winding is damaged
• Check compressor motor winding resistance
Yellow “ALERT” Welded Contactor 1. Compressor contactor has failed closed
Flash Code 8 Compressor always runs 2. Thermostat demand signal not connected to module
Yellow “ALERT” Low Voltage 1. Control circuit transformer is overloaded
Flash Code 9 Control circuit < 17VAC 2. Low line voltage (contact utility if voltage at disconnect is low)
• Check wiring connections
• Flash Code number corresponds to a number of LED flashes, followed by a pause and then repeated.
• TRIP and ALERT LEDs flashing at same time means control circuit voltage is too low for operation.
Status LED Status LED Description Status LED Troubleshooting Information
Diagnostic Description LED Status
Control Fault (No Power) Off
Normal Operation On
ASCD Delay Active
(with compressor demand) 1 Flash
Low Pressure Switch Lockout 2 Flashes
High Pressure Switch Lockout 3 Flashes
Ambient Sensor Fault 4 Flashes
Coil Sensor Fault 5 Flashes
Table 2. Control Diagnostic

12
Note: All units are shipped from the factory
with the default 70°F termination temperature
setting.
Defrost Test Procedure
1. Terminals “R”-”C” must have 18-30v present
between them in order for defrost sequences
to be initiated.
2 With heat mode thermostat demand (“Y”con-
nected to “R”), short (and hold) the “TEST”
pins together. This will energize reversing
valve to initiate a forced defrost. This will
bypass the ASCD and allow the high stage
compressor to come on immediately (if the
“REMOVE FOR NO DELAY” jumper at P6 is
removed). If the “REMOVE FOR NO DELAY”
jumper at P6 is installed, the compressor will
energize immediately following a 30-second
delay.
3. next remove the short on the “TEST” pins. If
the Coil temperature is above the Terminate
Temperature selection setting, the defrost
cycle will be terminated (reversing valve
will de-energized). If the coil temperature is
below the Terminate Temperature election
setting, the defrost cycle will continue for 14
minutes (or until the coil temperature rises
above the Terminate Temperature selection
setting). Short the “TEST” pins for 1 second
or more to force the control out of defrost
and back to heating mode (reversing valve
de-energized).Compressor will come on im-
mediately (if the “REMOVE FOR NO DELAY”
jumper is removed).If the“REMOVE FOR NO
DELAY” jumper is installed, the compressor
will energize immediately following a 30-
second delay.
Table 3. Module Wiring Troubleshooting
Miswired Module Indication Recommended Troubleshooting Action
Green LED is not on, Determine if both R and C module terminals are
module does not power up connected. Verify voltage is present at module’s R and
C terminals. Review 24VAC Power W iring (page 4) for
R and C wiring.
Green LED intermittent, Determine if R and Y terminals are wired in reverse.
module powers up only Verify module’s R and C terminals have a constant
when compressor runs source. Review 24VAC Power W iring (page 4) for R
and C wiring.
TRIP LED is on but system Verify Y terminal is connected to 24VAC at contactor
and compressor check OK coil. Verify voltage at contactor coil falls below 0.5VAC
when off. Verify 24 VAC is present across Y and C when
thermostat demand signal is present. If not, R and C are
reverse wired.
TRIP LED and ALERT LED Verify R and C terminals are supplied with 19-28VAC.
flashing together
ALERT Flash Code 3 Verify Y terminal is connected to 24VAC at contactor coil.
(Compressor Short Cycling) Verify voltage at contactor coil falls below 0.5VAC when
displayed incorrectly off.
ALERT Flash Code 5, 6 or 7 Check that compressor run and start wires are through
(Open Circuit, Open Start Circuit module’s current sensing holes. Verify Y terminal is
or Open Run Circuit) displayed connected to 24VAC at contactor coil. Verify voltage at
incorrectly contactor coil falls below 0.5VAC when off.
ALERT Flash Code 6 (Open Check that compressor run and start wires are routed
Start Circuit) displayed for Code 7 through the correct module sensing holes.
(Open Run Circuit) or vice versa
ALERT Flash Code 8 Determine if module’s Y terminal is connected. Verify Y
(Welded Contactor) terminal is connected to 24VAC at contactor coil. Verify
displayed incorrectly 24VAC is present across Y and C when thermostat demand
signal is present. If not, R and C are reverse wired. V erify
voltage at contactor coil falls below 0.5VAC when off.
Review Thermostat Demand Wiring (page 4) for Y and C
wiring.

13
Note: If the “Y2” thermostat input is energized
(on a 2-stage system), the second stage will
come on.
If the above steps will not initiate a defrost, replace
the defrost board.
Anti Short Cycle Timer Test
The 3-minute time delay feature can be bypassed
by shorting the “TEST” pins together.
Note: [Heating Mode] When the “TEST” pins are
shorted together for more than 1-second, the
control will switch between defrost mode and
heating mode (as described in the Defrost Test
Procedure section).
Note: [Cooling Mode] When the ‘TEST” pins are
shorted together for more than 1-second, the Anti
Short Cycle Timer will be bypassed.
Adjustment of Refrigerant Charge:
CAUTION:
Split system heat pump equipment
contains liquidand gaseousrefrigerant
under pressure. Adjustment of
refrigerant charge should only be
attempted by qualified, trained
personnel thoroughly familiar with the
equipment. Under no circumstances
should the homeowner attempt to
install and/or service this equipment.
Failure to comply with this warning
could result in equipment damage,
personal injury, or death.
NOTE: The unit must be charged while both first
and second stages are operating.
NOTE: To achieve rated capacity and efficiency
the compressor must be exposed to refrigerant
for at least 24 hours prior to running and then
must be run for a minimum of 12 hours.
NOTE: The following Refrigerant Charging
Charts are applicable to listed assemblies of
equipment and at listed airflows for the indoor
coil.Assemblies of indoor coils and outdoor units
not listed are not recommended.
Procedure for charging an R-410A
unit in AC mode at outdoor tempera-
tures above 65F.
1. With the system operating at steady-state,
measure the liquid refrigerant pressure in
psig at the service valve.
2. Measure the liquid refrigerant temperature
in Fahrenheit at the service valve.
3. For the temperature measured, determine
the required liquid refrigerant pressure from
the appropriate charging chart below.
4. If the pressure measured in step 1 is
greater than the required liquid refrigerant
pressure determined in step 4, then there
is too much charge in the system. Remove
refrigerant and repeat steps 1 through 3
until the system is correctly charged.
5. If the pressure measured in step 1 is less
than the required liquid refrigerant pressure
determined in step 4, then there is too little
charge in the system. Add refrigerant and
repeat steps 1 through 3 until the system
is correctly charged.
Procedure for charging an R-410A
unit in heating mode.
1. Evacuate the refrigerant system.
2. Weigh in the proper charge per Table 4
of these installation instructions using
the Heating Charging Chart as a guide.
Unit charge MUST be verified in cooling
season.
3. Ensure that the unit is operating properly
per the heating functional checkout in
these installation instructions.
Table 4. Split System
Heat Pump Charge
System Charge
Tonnage R-410A oz.
2 Ton 185
3 Ton 272
4 Ton 272
5 Ton 272

14
2 Ton System Cooling Charging Chart
3 Ton System Cooling Charging Chart
250
275
300
325
350
375
400
425
450
475
500
70 75 80 85 90 95 100 105 110 115 120 125
Liquid Temperature (F)
Liquid Pressure (psig)
A
dd refrigerent when below curve
Remove refrigerent when above curve
Cooling Charging Charts
250
275
300
325
350
375
400
425
450
475
70 75 80 85 90 95 100 105 110 115 120 125
Liquid Temperature (F)
Liquid Pressure (psig)
Add refrigerent when below curve
Remove refrigerent when above
curve

15
Cooling Charging Charts (continued)
4 Ton System Cooling Charging Chart
250
275
300
325
350
375
400
425
450
475
500
70 75 80 85 90 95 100 105 110 115 120 125
Liquid Temperature (F)
Liquid Pressure (psig)
A
dd refrigerent when below curve
Remove refrigerent when above curve
5 Ton System Cooling Charging Chart
250
275
300
325
350
375
400
425
450
475
500
70 75 80 85 90 95 100 105 110 115 120 125
Liquid Temperature (F)
Liquid Pressure (psig)
A
dd refrigerent when below curve
Remove refrigerent when above curve

INSTALLER: PLEASE LEAVE THESE
INSTALLATION INSTRUCTIONS WITH THE
HOMEOWNER.
7088680
Specifications and illustrations subject to change
without notice and without incurring obligations.
Printed in U.S.A. (04/08)
¢708868b¤
7088680
Heating Charging Chart
200
225
250
275
300
325
350
375
400
50 55 60 65 70 75 80 85 90
Liquid Temperature F
Liquid Pressure psig
Remove refrigerant when
above curve
Add refrigerant when
above curve