Daikin DZ16TC0361 User manual

I MPORTANT S AFETY I NSTRUCTIONS
Thefollowingsymbolsandlabelsareusedthroughoutthismanual
toindicateimmediateorpotentialsafetyhazards. Itistheowner’s
and installer’s responsibility to read and comply with all safety
information and instructions accompanying these symbols. Fail-
ure to heed safety information increases the risk of personal in-
jury, property damage, and/or product damage.
HIGH VOLTAGE!
D ISCONNECT ALL POWER BEFORE SERVICING .
M
ULTIPLE POWER SOURCES MAY BE PRESENT . F AILURE
TO DO SO MAY CAUSE PROPERTY DAMAGE , PERSONAL
INJURY OR DEATH .
WARNING
Only personnel that have been trained to install, adjust, service
or repair (hereinafter, “service”) the equipment specified in this
manual should service the equipment. The manufacturer will not
be responsible for any injury or property damage arising from
improper service or service procedures. If you service this unit,
you assume responsibility for anyinjury or property damage
which may result. In addition, in jurisdictions that require one or
more licenses to service the equipment specified in this manual,
only licensed personnel should service the equipment. Improper
installation, adjustment, servicing or repair of the equipment
specified in this manual, or attempting to install, adjust, service
or repair the equipment specified in this manual without proper
training may result in product damage, property damage,
personal injury or death.
S CROLL EQUIPPED UNITS SHOULD NEVER BE USED TO EVACUATE THE AIR
CONDITIONING SYSTEM . V ACUUMS THIS LOW CAN CAUSE INTERNAL
ELECTRICAL ARCING RESULTING IN A DAMAGED OR FAILED
COMPRESSOR .
CAUTION
CONDENSING UNIT
HEAT PUMP
INSTALLATION & SERVICE REFERENCE
S HIPPING I NSPECTION
Alwayskeeptheunitupright;layingtheunitonitssideortopmay
cause equipment damage. Shipping damage, and subsequent in-
vestigation is the responsibility of the carrier. Verify the model
number, specifications, electrical characteristics, and accesso-
ries are correct prior to installation. The distributor or manufac-
turer will not accept claims from dealers for transportation dam-
age or installation of incorrectly shipped units.
C ODES &R EGULATIONS
This product is designed and manufactured to comply with na-
tional codes. Installation in accordance with such codes and/or
prevailing local codes/regulations is the responsibility of the in-
staller. The manufacturer assumes no responsibility for equip-
ment installed in violation of any codes or regulations. Rated
performance is achieved after 72 hours of operation. Rated per-
formance is delivered at the specified airflow. See outdoor unit
specification sheet for split system models or product specifica-
tion sheet for packaged and light commercial models. Specifica-
tion sheets can be found at www.daikincomfort.com for Daikin
brand products. Within the website, please select the residen-
tial or commercial products menu and then select the submenu
forthetype ofproduct tobeinstalled, suchasairconditionersor
heat pumps, to access a list of product pages that each contain
links to that model’s specification sheet.
The United States Environmental Protection Agency (EPA) has is-
suedvariousregulationsregardingtheintroductionanddisposal
ofrefrigerants. Failureto followtheseregulationsmayharm the
environmentandcanleadtotheimpositionofsubstantialfines.
T HIS UNIT IS EQUIPPED WITH A 24VAC TRANSFORMER THAT POWERS
THE HEAT PUMP CONTROL BOARD . W HEN INSTALLED AS A
COMMUNICATING SYSTEM , ONLY 2 WIRES ARE NEEDED BETWEEN
INDOOR AND OUTDOOR EQUIPMENT . H OWEVER , WHEN INSTALLED AS
A NON - COMMUNICATING ( LEGACY ) SYSTEM , THE TRANSFORMER
WIRING ( LOW VOLTAGE AND LINE VOLTAGE ) MUST BE DISCONNECTED .
R
EFER TO THE LOW VOLTAGE WIRING SECTION FOR MORE DETAILS .
NOTICE
INSTALLATION INSTRUCTIONS
Ourcontinuingcommitmenttoqualityproductsmaymeanachangeinspecificationswithoutnotice.
©2013-2014, 2016-2017
5151 San Felipe St., Suite 500, Houston, TX 77056
www.daikincomfort.com
IOD-4009F
9/2017
“IMPORTANT-ThisproducthasbeendesignedandmanufacturedtomeetENERGYSTAR®
criteriaforenergyefficiencywhenmatchedwithappropriatecoilcomponents.However,
properrefrigerantchargeandproperairflowarecriticaltoachieveratedcapacityand
efficiency.Installationofthisproductshouldfollowthemanufacturer’srefrigerantcharging
andairflowinstructions. Failure toconfirmpropercharge and airflowmay reduce energy
efficiency and shorten equipment life.”

2
Should you have any questions please contact the local office of
theEPA.
If replacing a condensing unit or air handler, the system must be
manufacturerapprovedand AirConditioning,HeatingandRefrig-
erationInstitute(AHRI)matched. NOTE:Installationofunmatched
systems is strongly discouraged.
Outdoor units are approved for operation above 55°F in cooling
mode. Operation below 55°F in cooling mode requires the use of
an approved low ambient kit.
Operating the unit in a structure that is not complete (either as
part of new construction or renovation) is not covered under the
warranty.
F EATURES
This heat pump is a part of the ComfortNet™ family of products
and may be installed as part of a digitally communicating system.
The ComfortNet system provides enhanced setup features, and
enhanced diagnostics. It also reduces the number of thermostat
wires to a maximum of four and a minimum of two. This heat
pump may also be installed as part of a “legacy” system using a
standard 24 VAC thermostat.
I NSTALLATION C LEARANCES
Specialconsiderationmustbegiventolocation ofthe condensing
unit(s) in regard to structures, obstructions, other units, and any/
all other factors that may interfere with air circulation. Where
possible, the top of the unit should be completely unobstructed;
however, if vertical conditions require placement beneath an ob-
struction there should be a minimum of 60 inches between the
top of the unit and the obstruction(s). The specified dimensions
meet requirements for air circulation only. Consult all appropri-
ate regulatory codes prior to determining final clearances.
Another important consideration in selecting a location for the
unit(s)istheangletoobstructions. Eithersideadjacentthevalves
can be placed toward the structure provided the side away from
the structure maintains minimum service clearance. Corner in-
stallations are strongly discouraged.
OK!
OK!
AA AAA
A
CC
CCOK!
OK!
OK!
OK!
NOT
RECOMMENDED
AA
AA AA
AA
AA
B B B
B
Model Type A B C AA
Residential 10" 10" 18" 20"
Light Commercial 12" 12" 18" 24"
Minimum AirflowClearance
This unit can be located at ground floor level or on flat roofs. At
ground floor level, the unit must be on a solid, level foundation
that will not shift or settle. To reduce the possibility of sound
transmission, the foundation slab should not be in contact with
orbeanintegralpartofthebuildingfoundation.Ensurethefoun-
dation is sufficient to support the unit. A concrete slab raised
above ground level provides a suitable base.
R OOFTOP I NSTALLATIONS
Ifitisnecessary to installthisuniton a roof structure,ensurethe
roof structure can support the weight and that proper consider-
ation is given to the weather-tight integrity of the roof. Since the
unit can vibrate during operation, sound vibration transmission
should be considered when installing the unit. Vibration absorb-
ing pads or springs can be installed between the condensing unit
legs or frame and the roof mounting assembly to reduce noise
vibration.
NOTE: Theseunits requirespecial location consideration in areas
of heavy snow accumulation and/or areas with prolonged
continuoussubfreezingtemperatures.Heatpumpunitbaseshave
cutouts under the outdoor coil that permit drainage of frost
accumulation. Situate the unit to permit free unobstructed
drainage of the defrost water and ice. A minimum 3” clearance
under the outdoor coil is required in the milder climates.
Inmoresevereweatherlocations,itisrecommendedthattheunit
be elevated to allow unobstructed drainage and air flow. The
following elevation minimums are recommended:

3
DesignTemperature SuggestedMinimumElevation
+15° and above 2 1/2"
-5° to+14° 8"
below -5° 12"
S AFE R EFRIGERANT H ANDLING
Whiletheseitemswillnotcover every conceivable situation,they
should serve as a useful guide.
T O AVOID POSSIBLE INJURY , EXPLOSION OR DEATH , PRACTICE SAFE
HANDLING OF REFRIGERANTS .
WARNING
R EFRIGERANTS ARE HEAVIER THAN AIR . T HEY CAN “ PUSH OUT ” THE
OXYGEN IN YOUR LUNGS OR IN ANY ENCLOSED SPACE . T O AVOID
POSSIBLE DIFFICULTY IN BREATHING OR DEATH :
•N
EVER PURGE REFRIGERANT INTO AN ENCLOSED ROOM OR SPACE .B Y
LAW , ALL REFRIGERANTS MUST BE RECLAIMED .
•I
F AN INDOOR LEAK IS SUSPECTED , THOROUGHLY VENTILATE THE AREA
BEFORE BEGINNING WORK .
•L
IQUID REFRIGERANT CAN BE VERY COLD .T O AVOID POSSIBLE FROST BITE
OR BLINDNESS , AVOID CONTACT AND WEAR GLOVES AND GOGGLES .I F
LIQUID REFRIGERANT DOES CONTACT YOUR SKIN OR EYES , SEEK MEDICAL
HELP IMMEDIATELY .
•A
LWAYS FOLLOW EPA REGULATIONS .N EVER BURN REFRIGERANT , AS
P
OISONOUS GAS WILL BE PRODUCED .
WARNING
T O AVOID POSSIBLE EXPLOSION :
•N
EVER APPLY FLAME OR STEAM TO A REFRIGERANT CYLINDER .I F YOU
MUST HEAT A CYLINDER FOR FASTER CHARGING , PARTIALLY IMMERSE IT
IN WARM WATER .
•N
EVER FILL A CYLINDER MORE THAN 80% FULL OF LIQUID REFRIGERANT .
•N
EVER ADD ANYTHING OTHER THAN R-22 TO AN R-22 CYLINDER OR R-
410A
TO AN R-410A CYLINDER .T HE SERVICE EQUIPMENT USED MUST
BE LISTED OR CERTIFIED FOR THE TYPE OF REFRIGERANT USED .
•S
TORE CYLINDERS IN A COOL , DRY PLACE .N EVER USE A CYLINDER AS A
P
LATFORM OR A ROLLER .
WARNING
T O AVOID POSSIBLE EXPLOSION , USE ONLY RETURNABLE ( NOT
DISPOSABLE ) SERVICE CYLINDERS WHEN REMOVING REFRIGERANT FROM
A SYSTEM .
•E
NSURE THE CYLINDER IS FREE OF DAMAGE WHICH COULD LEAD TO A
LEAK OR EXPLOSION .
•E
NSURE THE HYDROSTATIC TEST DATE DOES NOT EXCEED 5 YEARS .
•E
NSURE THE PRESSURE RATING MEETS OR EXCEEDS 400 PSIG .
W
HEN IN DOUBT , DO NOT USE CYLINDER .
WARNING
R EFRIGERANT L INES
T HE COMPRESSOR POE OIL FOR R-410A UNITS IS EXTREMELY
SUSCEPTIBLE TO MOISTURE ABSORPTION AND COULD CAUSE
COMPRESSOR FAILURE . D O NOT LEAVE SYSTEM OPEN TO ATMOSPHERE
ANY LONGER THAN NECESSARY FOR INSTALLATION .
CAUTION
Use only refrigerant grade (dehydrated and sealed) copper tubing
to connect the condensing unit with the indoor evaporator. After
cutting the tubing, install plugs to keep refrigerant tubing clean
and dry prior to and during installation. Tubing should always be
cut square keeping ends round and free from burrs. Clean the
tubing to prevent contamination.
DoNOTletrefrigerantlinescomeindirectcontactwithplumbing,
ductwork, floor joists, wall studs, floors, and walls. When run-
ning refrigerant lines through a foundation or wall, openings
should allow for sound and vibration absorbing material to be
placed or installed between tubing and foundation. Any gap be-
tween foundation or wall and refrigerant lines should be filled
with a pliable silicon-based caulk, RTV or a vibration damping
material.Avoidsuspendingrefrigeranttubingfromjoistsandstuds
with rigid wire or straps that would come in contact with the
tubing. Use an insulated or suspension type hanger. Keep both
lines separate and always insulate the suction line.
These sizes are suitable for line lengths of 79 feet or less. If a run
ofmore thaneighty feet is required, refer to Remote Cooling Ser-
vice Manual, or TP-106 Long Line Set Application R-22, or TP-107
Long Line Set Application R-410A or contact your distributor for
assistance.
Cond
Unit
Tons Suct Liq Suct Liq Suct Liq
11/2 5/8 1/4 3/4 3/8 3/4 3/8
2 5/81/43/43/83/43/8
21/2 5/8 1/4 3/4 3/8 7/8 3/8
3 3/4 3/8 7/8 3/8 1 1/8 3/8
31/2 7/8 3/8 11/8 3/8 1 1/8 3/8
4 7/8 3/8 1 1/8 3/8 1 1/8 3/8
5 7/8 3/8 1 1/8 3/8 1 1/8 3/8
Line Diameter (In.OD)
RECOMMENDED INTERCONNECTING TUBING (Ft)
0-24 25-49 50-79*
* Lines greater than 79 feet in length or vertical elevation changes more
than50feetrefer to theRemoteCoolingServiceManualorcontactyour
distributor for assistance.
Insulation is necessary to prevent condensation from forming
and dropping from the suction line. Armaflex (or satisfactory
equivalent) with 3/8” min. wall thickness is recommended. In
severe conditions (hot, high humidity areas) 1/2” insulation may
be required. Insulation must be installed in a manner which
protects tubing from damage and contamination.
Where possible, drain as much residual compressor oil from ex-
isting systems, lines, and traps; pay close attention to low areas
whereoilmaycollect. NOTE:Ifchangingrefrigeranttypes,ensure
theindoorcoilandmeteringdeviceiscompatiblewiththetypeof
refrigerantbeingused;otherwise,theindoorcoilmustbereplaced.

4
B URYING R EFRIGERANT L INES
If burying refrigerant lines can not be avoided, use the following
checklist.
1. Insulate liquid and suction lines separately.
2. Enclose all underground portions of the refrigerant lines
in waterproof material (conduit or pipe) sealing the ends
wheretubing enters/exits the enclosure.
3. If the lines must pass under or through a concrete slab,
ensure lines are adequately protected and sealed.
R EFRIGERANT L INE C ONNECTIONS
IMPORTANT
To avoid overheating the service valve, TXV valve, or filter
drier while brazing, wrap the component with a wet rag, or
use a thermal heat trap compound. Be sure to follow the
manufacturer’s instruction when using the heat trap
compound.Note:RemoveSchradervalvesfromservicevalves
beforebrazingtubestothevalves.Useabrazingalloyof2%
minimumsilvercontent. Donot useflux.
Torch heat required to braze tubes of various sizes is
proportional to the size of the tube. Tubes of smaller size
require less heat to bring the tube to brazing temperature
before adding brazing alloy. Applying too much heat to any
tube can melt the tube. Service personnel must use the
appropriateheatlevelforthesizeofthetubebeingbrazed.
NOTE:Theuseofaheatshieldwhenbrazingisrecommended
toavoid burning the serial plate or the finish on the unit.
1. The ends of the refrigerant lines must be cut square,
deburred, cleaned, and be round and free from nicks or
dents. Any other condition increases the chance of a
refrigerant leak.
2. “Sweep” the refrigerant line with nitrogen or inert gas
during brazing to prevent the formation of copper-oxide
inside the refrigerant lines. The POE oils used in R-410A
applications will clean any copper-oxide present from the
insideofthe refrigerant linesand spread itthroughout the
system.Thismaycauseablockageorfailureofthemetering
device.
3. Afterbrazing,quenchthejointswithwaterorawetclothto
preventoverheating ofthe servicevalve.
4. Ensure the filter drier paint finish is intact after brazing. If
the paint of the steel filter drier has been burned or
chipped, repaint or treat with a rust preventative. This is
especially important on suction line filter driers which
are continually wet when the unit is operating.
NOTE: Be careful not to kink or dent refrigerant lines. Kinked or
dentedlines willcausepoorperformanceorcompressordamage.
Do NOT make final refrigerant line connection until plugs are
removed from refrigerant tubing.
NOTE: Before brazing, verify indoor TXV is correct for R410A and
proper size.
L EAK T ESTING (N ITROGEN OR N ITROGEN -T RACED )
T O AVOID THE RISK OF FIRE OR EXPLOSION , NEVER USE OXYGEN , HIGH
PRESSURE AIR OR FLAMMABLE GASES FOR LEAK TESTING OF A
REFRIGERATION SYSTEM .
WARNING
T O AVOID POSSIBLE EXPLOSION , THE LINE FROM THE NITROGEN
CYLINDER MUST INCLUDE A PRESSURE REGULATOR AND A PRESSURE
RELIEF VALVE . T HE PRESSURE RELIEF VALVE MUST BE SET TO OPEN AT
NO MORE THAN 150 PSIG .
WARNING
Pressure test the system using dry nitrogen and soapy water to
locate leaks. If you wish to use a leak detector, charge the system
to 10 psi using the appropriate refrigerant then use nitrogen to
finish charging the system to working pressure then apply the
detector to suspect areas. If leaks are found, repair them. After
repair, repeat the pressure test. If no leaks exist, proceed to sys-
temevacuation.
S YSTEM E VACUATION
Condensing unit liquid and suction valves are closed to contain
the charge within the unit. The unit is shipped with the valve
stems closed and caps installed. Do not open valves until the
systemisevacuated.
REFRIGERANT UNDER PRESSURE!
F AILURE TO FOLLOW PROPER PROCEDURES MAY CAUSE PROPERTY
DAMAGE , PERSONAL INJURY OR DEATH .
WARNING
NOTE: Scroll compressors should never be used to evacuate or
pump down a heat pump or air conditioning system.

5
P ROLONGED OPERATION AT SUCTION PRESSURES LESS THAN 20 PSIG
FOR MORE THAN 5 SECONDS WILL RESULT IN OVERHEATING OF THE
SCROLLS AND PERMANENT DAMAGE TO THE SCROLL TIPS , DRIVE
BEARINGS AND INTERNAL SEAL .
CAUTION
1. Connect the vacuum pump with 250 micron capability to
the service valves.
2. Evacuate the system to 250 microns or less using suction
and liquid service valves. Using both valves is necessary
as some compressors create a mechanical seal separating
thesides of the system.
3. Close pump valve and hold vacuum for 10 minutes.
Typically pressure will rise during this period.
• Ifthepressure risesto1000 micronsorless andremains
steady the system is considered leak-free; proceed to
startup.
• If pressure rises above 1000 microns but holds steady
below 2000 microns, moisture and/or noncondensibles
may be present or the system may have a small leak.
Returntostep2:Ifthesameresultisencountered check
for leaks as previously indicated and repair as necessary
thenrepeatevacuation.
• If pressure rises above 2000 microns, a leak is present.
Check for leaks as previously indicated and repair as
necessary then repeat evacuation.
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
0 1 2 3 4 5 6 7 8 9 10
LEAK(S)
PRESENT
MINUTES
VACUUM IN MICRONS
CONDENSIBLES OR SMALL
LEAK PRESENT
NO LEAKS
NO CONDENSIBLES
E LECTRICAL C ONNECTIONS
HIGH VOLTAGE!
D ISCONNECT ALL POWER BEFORE SERVICING .
M
ULTIPLE POWER SOURCES MAY BE PRESENT . F AILURE
TO DO SO MAY CAUSE PROPERTY DAMAGE , PERSONAL
INJURY OR DEATH DUE TO ELECTRIC SHOCK . W IRING
MUST CONFORM WITH NEC OR CEC AND ALL LOCAL
CODES . U NDERSIZED WIRES COULD CAUSE POOR
EQUIPMENT PERFORMANCE , EQUIPMENT DAMAGE OR
FIRE .
WARNING
T O AVOID THE RISK OF FIRE OR EQUIPMENT DAMAGE , USE COPPER
CONDUCTORS .
WARNING
The condensing unit rating plate lists pertinent electrical data
necessary for proper electrical service and overcurrent protec-
tion. Wires should be sized to limit voltage drop to 2% (max.)
fromthemain breaker or fusepanelto the condensingunit. Con-
sulttheNEC,CEC,andalllocalcodestodeterminethecorrectwire
gaugeandlength.
Local codes often require a disconnect switch located near the
unit;do notinstalltheswitchonthe unit. Refer totheinstallation
instructions supplied with the indoor furnace/air handler for spe-
cific wiring connections and indoor unit configuration. Likewise,
consulttheinstructionspackagedwiththe thermostatformount-
ing and location information.
O VERCURRENT P ROTECTION
The following overcurrent protection devices are approved for
use.
• Time delay fuses
• HACR type circuit breakers
Thesedeviceshavesufficienttimedelaytopermitthemotor-com-
pressor to start and accelerate its load.
H IGH V OLTAGE C ONNECTIONS
Route power supply and ground wires through the high voltage
port and terminate in accordance with the wiring diagram pro-
vided inside the control panel cover.
L OW V OLTAGE C ONNECTIONS
This heat pump is equipped with a factory-installed transformer
to power the outdoor controls when installed as part of a fully
communicating HVAC system utilizing a ComfortNet™ compatible
indoor unit. In this configuration only two low voltage control
wires are required between the outdoor unit and indoor unit.
The unit also has legacy 24 VAC inputs to support non-communi-
cating systems. When this configuration is used, the transformer
in the outdoor unit must be disconnected from the low voltage
and line voltage connections. The transformer connecting wires
can then be discarded. Route control wires through the low volt-
age port and terminate in accordance with the wiring diagram
provided inside the control panel cover.

6
HIGH
VOLTAGE
PORT
LOW
VOLTAGE
PORT
VoltagePorts
NOTE: For two-stage units, refer to the Installation Instructions
supplied with the variable speed indoor units for field wiring
connections.
NOTE: Iftheheatpumpunitiswiredinthecommunicatingmode
together with the compatible communicating indoor unit, the
communicating equipment is able to search and identify the
condensingunitwhenpowerisappliedtothesystem.Refertothe
Installation Manual of the communicating indoor equipment for
more information.
Use the dipswitch to select defrost time interval (30, 60, 90, 120
minutes;seechartbelow).
Factorydefault setting is 30 minutes. The maximum defrost cycle
time is 10 minutes.
60 30
0
30 Minutes
60
60 30
0
60 Minutes
60
120 Minutes
60 30
0
90 Minutes
60
60 30
0
60
Dipswitch Settings for Selection of Defrost Time
S YSTEM S TART U P
POSSIBLE REFRIGERANT LEAK!
T O AVOID A POSSIBLE REFRIGERANT LEAK , OPEN THE SERVICE VALVES
UNTIL THE TOP OF THE STEM IS 1/8” FROM THE RETAINER .
CAUTION
NOTE: Power must be supplied to the 18 SEER outdoor units
containingECM motors before the power is applied to the indoor
unit. Sending a low voltage signal without high voltage power
present at the outdoor unit can cause malfunction of the control
moduleontheECMmotor.
Adequaterefrigerant charge for the matching evaporator coil or
air handler and 15 feet of lineset is supplied with the condensing
unit. If using evaporator coils or air handlers other than HSVTC
coil it maybe necessary to add or remove refrigerant to attain
proper charge. If line set exceeds 15 feet in length, refrigerant
should be added at .6 ounces per foot of liquid line.
NOTE: Charge should always be checked using superheat when
using a piston and subcooling when using TXV equipped indoor
coil to verify proper charge.
Open the suction service valve first! If the liquid service valve is
opened first, oil from the compressor may be drawn into the in-
door coil TXV, restricting refrigerant flow and affecting operation
ofthesystem.
When opening valves with retainers, open each valve only until
the top of the stem is 1/8” from the retainer. To avoid loss of
refrigerant,DONOTapplypressureto theretainer.Whenopening
valves without a retainer remove service valve cap and insert a
hex wrench into the valve stem and back out the stem by turning
thehexwrenchcounterclockwise.Openthevalveuntilitcontacts
the rolled lip of the valve body.
NOTE: These are not back-seating valves. It is not necessary to
force the stem tightly against the rolled lip.
After the refrigerant charge has bled into the system, open the
liquid service valve. The service valve cap is the secondary seal
for the valve and must be properly tightened to prevent leaks.
Make sure cap is clean and apply refrigerant oil to threads and
sealing surface on inside of cap. Tighten cap finger-tight and then
tightenadditional1/6ofaturn(1wrenchflat)toproperlyseatthe
sealing surfaces.
Do not introduce liquid refrigerant from the cylinder into the
crankcaseofthecompressorasthismaydamagethecompressor.
1. Break vacuum by fully opening liquid and suction base
valves.
2. Set thermostat to call for cooling. Check indoor and
outdoor fan operation and allow system to stabilize for 10
minutes for fixed orifices and 20 minutes for expansion
valves.
C HARGE V ERIFICATION
REFRIGERANT UNDER PRESSURE!
• D O NOT OVERCHARGE SYSTEM WITH REFRIGERANT .
• D
O NOT OPERATE UNIT IN A VACUUM OR AT NEGATIVE PRESSURE .
F
AILURE TO FOLLOW PROPER PROCEDURES MAY CAUSE PROPERTY
DAMAGE , PERSONAL INJURY OR DEATH .
WARNING

7
U SE REFRIGERANT CERTIFIED TO AHRI STANDARDS . U SED REFRIGERANT
MAY CAUSE COMPRESSOR DAMAGE , AND IS NOT COVERED UNDER THE
WARRANTY . M OST PORTABLE MACHINES CANNOT CLEAN USED
REFRIGERANT TO MEET AHRI STANDARDS .
CAUTION
V IOLATION OF EPA REGULATIONS MAY RESULT IN FINES OR OTHER
PENALTIES .
NOTICE
O PERATING THE COMPRESSOR WITH THE SUCTION VALVE CLOSED MAY
CAUSE SERIOUS COMPRESSOR DAMAGE .
CAUTION
F INAL C HARGE A DJUSTMENT
The outdoor temperature must be 60°F or higher. Set the room
thermostattoCOOL,fanswitchtoAUTO,andsetthetemperature
controlwellbelowroomtemperature.
After system has stabilized per startup instructions, check sub-
cooling and superheat as detailed in the following section.
E XPANSION V ALVE S YSTEM
T O PREVENT PERSONAL INJURY , CAREFULLY CONNECT AND DISCONNECT
MANIFOLD GAUGE HOSES . E SCAPING LIQUID REFRIGERANT CAN CAUSE
BURNS . D O NOT VENT REFRIGERANT INTO THE ATMOSPHERE . R ECOVER
ALL REFRIGERANT DURING SYSTEM REPAIR AND BEFORE FINAL UNIT
DISPOSAL .
CAUTION
NOTE:Unitsmatchedwithindoorcoilsequippedwithnon-adjust-
ableTXVshouldbechargedbysubcoolingonly.
Run the unit on low stage cooling for 10 minutes until refrigerant
pressures stabilize. Use the following guidelines and methods to
checkunitoperationandensurethattherefrigerantchargeiswithin
limits. Charge the unit on low stage.
1. Purgegauge lines.Connectservice gauge manifoldto base-
valveserviceports.Run system at least10minutesto allow
pressure to stabilize.
2. Temporarily install a thermometer on the liquid line at the
liquid line service valve and 4-6" from the compressor on
the suction line. Ensure the thermometer makes adequate
contact and is insulated for best possible readings. Use
liquid line temperature to determine subcooling and vapor
temperaturetodeterminesuperheat.
LIQUIDPRESSURE
PSIG R-22 R-410A
200 101 70
210 105 73
220 108 76
225 110 78
235 113 80
245 116 83
255 119 85
265 121 88
275 124 90
285 127 92
295 130 95
305 133 97
325 137 101
355 144 108
375 148 112
405 155 118
415 157 119
425 n/a 121
435 n/a 123
445 n/a 125
475 n/a 130
500 n/a 134
525 n/a 138
550 n/a 142
575 n/a 145
600 n/a 149
625 n/a 152
SATURATED LIQUID PRESSURE
TEMPERATURECHART
SATURATED LIQUID
TEMPERATURE ºF
SUCTION PRESSURE
PSIG R-22 R-410A
50 26 1
52 28 3
54 29 4
56 31 6
58 32 7
60 34 8
62 35 10
64 37 11
66 38 13
68 40 14
70 41 15
72 42 16
74 44 17
76 45 19
78 46 20
80 48 21
85 50 24
90 53 26
95 56 29
100 59 31
110 64 36
120 69 41
130 73 45
140 78 49
150 83 53
160 86 56
170 90 60
SATURATED SUCTION PRESSURE
TEMPERATURECHART
SATURATED SUCTION
TEMPERATURE ºF

8
3. Check subcooling and superheat. Systems with TXV
application should have a subcooling of 6°F +/- 1°F and
superheatof8°F+/-1°F.
a. If subcooling and superheat are low, adjust TXV to
8°F +/- 1°F superheat, then check subcooling.
NOTE: To adjust superheat, turn the valve stem clock-
wise to increase and counter clockwise to decrease.
b. If subcooling is low and superheat is high, add charge
toraise subcooling to 6°F+/-1°F then check superheat.
c. If subcooling and superheat are high, adjust TXV valve
to8°F +/- 1°Fsuperheat, then check subcooling.
d. If subcooling is high and superheat is low, adjust TXV
valve to 8°F +/- 1°F. superheat and remove charge to
lower the subcooling to 6°F +/- 1°F.
NOTE:DoNOTadjustthechargebasedonsuctionpressure
unless there is a gross undercharge.
4. Disconnect manifold set, installation is complete.
SUBCOOLING FORMULA = SAT. LIQUID TEMP. - LIQUID LINE TEMP.
NOTE: ChecktheSchraderportsforleaksandtightenvalvecores
if necessary. Install caps finger-tight.
H EAT P UMP - H EATING C YCLE
Thepropermethodofchargingaheatpumpintheheatmodeisby
weight with the additional charge adjustments for line size, line
length,andothersystemcomponents. Forbestresultsonoutdoor
units with TXVs, superheat should be 5°F +/- 1°F at 4-6" from the
compressor. Make final charge adjustments in the cooling cycle.
ADDITIONAL NOTES
1. There are (3) 7-segment LED displays on the PCB. Refer to
the Troubleshooting chart at the end of this manual for
definitions of the LED status.
2. “TERM” dip switch is used for communications bus
configuration. Leave the settings to the factory default
position.
3. “LEARN” push button is used to reset the commnications
between the equipment. Used only for troubleshooting
purposes.
4. Press “TEST” push button, during system “Standby” mode
to turn on both the compressor and outdoor fan for five
seconds.
5. The “RECALL” push button is used to retrieve the six most
recent faults. The control must be in Standby Mode (no
thermostat inputs) to use the feature. Depress the push
button for approximately two seconds and less than five
seconds. The 7-segment LED displays will then display the
sixmostrecent faults beginningwith the mostrecent fault
and decrementing to the least recent fault. The faults may
be cleared by depressing the button for greater than five
seconds. Consecutively repeated faults are displayed a
maximumofthreetimes.Refertothefaultcodedefinitions
at the end of this manual for more details.
6. A forced defrost can be initiated by pressing “TEST” and
“RECALL” push buttons simultaneously for more than 1
secondwith a valid call for heat. The forced defrost can be
terminatedby
• A 10 minute lapse in time,
• A coil temperature rise above 75°F or
• Bypressingthetwobuttonsagainformorethan1sec-
ond.
C OMFORT N ET ™S YSTEM
O VERVIEW
The ComfortNet system is a system that includes a ComfortNet
compatible air handler/furnace/modular blower and air condi-
tionerorheatpump. Anyothersystemconfigurationsareconsid-
eredinvalid ComfortNet systemsand must beconnected asa tra-
ditional (or legacy) system.
AComfortNetheating/airconditioningsystemdiffersfromalegacy/
traditional system in the manner in which the indoor unit, out-
door unit and thermostat interact with one another. In a tradi-
tionalsystem,thethermostat sends commandstotheindoor and
outdoor units via analog 24 VAC signals. It is a one-way commu-
nication path in that the indoor and outdoor units typically do
notreturn informationtothethermostat.
Ontheotherhand,theindoorunit,andoutdoorunitcomprisinga
ComfortNet system “communicate” digitally with one another. It
is now a two-way communications path. The thermostat still
sends commands to the indoor and outdoor units. However, the
indoor and outdoor units may also request and receive informa-
tionfromoneanotherto optimize systemperformance.
Two-way digital communications is accomplished using only two
wiresbetweentheindoorandoutdoorunits. Theheatpumpcon-
trol board is powered by 24 VAC, which is supplied by the factory-
installed transformer in the heat pump control box. (If you are
attempting to install a CTK0* thermostat, installation
instructions can be found at www.comfortcontrols.com/#instal-
lation.)
AIRFLOWCONSIDERATION
Airflow demands are managed differently in a fully communicat-
ing system than they are in a legacy wired system. The system
operating mode (as determined by the thermostat) determines
which unit calculates the system airflow demand. If the indoor
unit is responsible for determining the airflow demand, it calcu-
lates the demand and sends it to the ECM motor. If the outdoor
unit or thermostat is responsible for determining the demand, it
calculates the demand and transmits the demand along with a
fan request to the indoor unit. The indoor unit then sends the
demand to the ECM motor. The table below lists the various
ComfortNet systems, the operating mode, and airflow demand
source.

9
System SystemOperating
Mode Airflow DemandSource
Cooling HeatPump
Heat Pump Heating
Only HeatPump
HP + Electric Heat
Strips >ofHeatPumporAir HandlerDemand
Electric Heat Strips
Only Air Handler
ContinuousFan Thermostat
Cooling HeatPump
Heat Pump Heating
Only HeatPump
Auxiliary Heating Furnace
ContinuousFan Thermostat
HeatPump+ Air
Handler
Heat Pump+
Furnace
Forexample,assumethesystemis aheatpumpmatchedwith an
air handler. With a call for low stage cooling, the heat pump will
calculate the system’s low stage cooling airflow demand. The
heat pump will then send a fan request along with the low stage
coolingairflowdemand to the air handler. Oncereceived,the air
handler will send the low stage cooling airflow demand to the
ECM motor. The ECM motor then delivers the low stage cooling
airflow. The table at right lists the nominal high and low stage
airflowfortheComfortNet™heatpumps.
High Low High Low
DZ16TC0241 800 600 800 600
DZ16TC0361 1200 800 1200 800
DZ16TC0481 1550 1100 1550 1100
DZ16TC0601 1800 1210 1800 1210
DZ18TC0241 850 550 850 550
DZ18TC0361 1250 850 1250 850
DZ18TC0481 1750 1210 1750 1210
DZ18TC0601 1750 1210 1750 1210
Models Cooling Heating
CONTROL WIRING
NOTE: Refer to section Electrical Connections - High Voltage
Connectionsfor208/230voltlineconnectionstotheairconditioner
orheatpump.
NOTE: Aremovable plug connector is provided with the control
board to make thermostat wire connections. This plug may be
removed, wire connections made to the plug, and replaced. It is
strongly recommended that you do not connect multiple wires
intoa single terminal. Wirenuts arerecommended to ensure one
wire is used for each terminal. Failure to do so may result in
intermittentoperation.
Typical 18 AWG thermostat wire may be used to wire the system
components. 150 feet is the maximum recommended length of
wire between indoor unit and outdoor unit, or between indoor
unit and thermostat.
When installed as a communicating system, only data lines 1 and
2 are required between the indoor and outdoor units.
R
C
G
Y
Optional
Optional
Optional if
feature
supported by
thermostat
INDOOR
BOARD TERMINAL
CONNECTIONS
OUTDOOR
BOARD TERMINAL
CONNECTIONS
OUTDOOR
TRANSFORMER
1
2
C
R
C
G
Y
1
2
C
LEGACY CONTROLS WIRING
The intergrated control board on this unit is factory-equipped
with a 4-pin connector for low voltage contols wiring for commu-
nicating systems. If the system is installed as a non-communicat-
ing (legacy) system, remove the 4-pin connector and disconnect
the transformer low voltage and line voltage wiring. Then, install
the 7-pin connector that is supplied in the literature/accessories
bagintothe intergrated controlboard in theappropriate location
indicated by the color-coded labels found on both the control
board and pin connector plug.
RCG O
RCG O
RCG O
12
System Wiring for legacy controls
COMFORTNET™SYSTEM ADVANCED FEATURES
TheComfortNetsystempermitsaccesstoadditionalsysteminfor-
mation, advanced setup features, and advanced diagnostic/
troubleshooting features. See indoor equipment installation
manual for directions on how to access the menus.

10
•Profile D rampsupto50%of the demandfor1/2 minute,then
ramps to 82% of the full cooling demand airflow and operates
thereforapproximately71/2minutes. Themotorthenstepsup
to the full demand airflow. Profile D has a 1/2 minute at 50%
airflow OFF delay.
OFF
OFF
AirflowTables
STATUS
The current system operational mode and requested indoor CFM
isreportedinthismenu. Thisinformationcanbeusedfortrouble-
shooting purposes.
HEAT SET-UP
This menu allows for the adjustment of several heating perfor-
mancevariables.HeatAirflowTrim(rangefrom-10%to10%in2%
increments),HeatFanONDelay,HeatFanOFFDelay,DefrostInter-
val and Compressor Delay can be adjusted in this menu. Defrost
Intervaldeterminesthe amount ofcompressorrun time between
defrost cycles. Compressor delay selects a compressor off time
after a reversing valve shift.
THERMOSTATMENU
If this heat pump is installed with a CT compatible furnace, the
system is recognized as a dual fuel system. The balance point
temperature should be set via the thermostat. See thermostat
instruction manual for details on how to set the balance point.
NETWORKTROUBLESHOOTING
Verify that the bus TERM dipswitches are in the ON position.
1
2
OFF ON
TERM
TERM
DIAGNOSTICS
Accessing the air conditioner/heat pump’s diagnostics menu pro-
vides ready access to the last six faults detected by the air condi-
tioner/heat pump. Faults are stored most recent to least recent.
Any consecutively repeated fault is stored a maximum of three
times. Example: The power supply to the air conditioner/heat
pump is continuously below 187 VAC. The control will only store
this fault the first three consecutive times the fault occurs.
NOTE: It is highly recommended that the fault history be cleared
after performing maintenance or servicing the heat pump.
IDENTIFICATION
ModelNumber,SerialNumberandSoftwareVersionaredisplayed
withinthismenu.Amodelnumbercheckwillhelpdetermineifthe
equipmentshareddataiscorrectfortheunit.Ifthemodelnumber
isnotcorrect,eventhoughveryrare,amemorycardisavailableto
loadtheproperdata.
SENSORS
The outdoor ambient temperature and coil temperature are dis-
played in the Sensor Menu. This information can be used for
troubleshooting purposes.
COOLSET-UP
This menu allows for the adjustment of several cooling perfor-
mance variables. Cool Airflow Trim (range from -10% to 10% in
2% increments), Cool Airflow Profiles, Cool Fan ON Delay, Cool
Fan OFF Delay and Dehumidification Select (enable or disable
dehumidification) can be adjusted in this menu. See the follow-
ing images showing the four cooling airflow profiles.
•ProfileA(default)providesonlyanOFFdelayofone(1)minute
at 100% of the cooling demand airflow.
OFF
100% CFM 100% CFM
1 min
OFF
•Profile B ramps up to full cooling demand airflow by first
stepping up to 50% of the full demand for 30 seconds. The
motor then ramps to 100% of the required airflow. A one (1)
minute OFF delay at 100% of the cooling airflow.
50% CFM
1/2 min
100% CFM 100% CFM
1 min
OFF OFF
•Profile C ramps up to 82% of the full cooling demand airflow
andoperatesthereforapproximately71/2minutes. Themotor
then steps up to the full demand airflow. Profile C also has a
one(1)minute100%OFFdelay.
100% CFM
OFF OFF

11
The ComfortNet™ system is a fully communicating system which
operates over a communicating network. Occasionally the need
to troubleshoot the network may arise. The integrated control
module has some on-board tools that may be used to trouble-
shoot the network. These tools are: red communications LED,
greenreceive(Rx)LED,andlearnbutton.
• Red communications LED - Indicates the status of the
network. The table below indicates the LED status and
the corresponding potential problem.
• Green receive LED - Indicates network traffic. The table
below indicates the LED status and the corresponding
potential problem.
• LEARN button - Used to reset the network. Depress the
buttonforapproximately2secondstoresetthenetwork.
SYSTEMTROUBLESHOOTING
NOTE: RefertotheinstructionsaccompanyingtheCTcompatible
indoor air handler/furnace/modular blower unit for
troubleshooting information regarding indoor unit diagnostics..
Refer to the Troubleshooting Chart at the end of this manual for a
listing of possible air conditioner and heat pump error codes,
possible causes and corrective actions.

12
LED LED Status Indication Possible Causes Corrective Action(s) Notes & Cautions
Off • Normal condition • None • None • None
• Depress once quickly for a
power-up reset
• Depress and hold for 2
seconds for an out-of-box
reset
• Control power up
• Learn button depressed
• No power • No power to furnace • Check fuses and circuit
breakers; replace/reset
• Communications error • Open fuse • Replace blown fuse
• Communications error • Check for shorts in low
voltage wiring in
heat pump/system
• Reset network by
depressing learn button
• Check data 1/ data 2
voltages
• Broken/ disconnected data
wire(s) • Check communications wiring (data 1/ data 2
wires)
• Turn power OFF prior to
repair
• Heat pump is installed as a
legacy/ traditional system • Check wire connections at terminal block • Verify wires at terminal blocks are securely twisted
together prior to inserting
into terminal block
• Verify heat pump
installation type (legacy/
traditional or
communicating)
• Check data 1/ data 2
voltages
Rapid Flashing • Normal network traffic • Control is “talking” on
network as expected • None • None
• Data 1 and data 2 wires reversed
at heat pump, thermostat, or
CT compatible indoor unit
• Check communications
wiring (data 1/ data 2
wires)
• Turn power OFF prior to
repair
• Short between data 1 and
data 2 wires • Check wire connections at terminal block • Verify wires at terminal blocks are securely twisted
together prior to inserting
into terminal block
• Short between data 1 or
data 2 wires and R
(24VAC) or C (24VAC
common)
• Check data 1/ data 2
voltages
2 Flashes • Out-of-box reset • None
1 Flash • Communications Failure • Communications Failure
• None
Green Receive LED
Off • Turn power OFF prior to
repair
1 Steady Flash • No network found
On Solid • Data 1/ Data 2 miss-wire
Red Communications
LED
• Depress Learn Button

13
TROUBLESHOOTING INFORMATION: CONDENSING UNIT
For detailed service information refer to the Remote Condensing Unit Service manual.
Complaint System Operating
Pressures
POSSIBLE CAUSE
DOTS IN ANALYSIS
GUIDE INDICATE
"POSSIBLE CAUSE"
SYMPTOM
System will not start Compressor will not start - fan runs Comp. and Cond. Fan will not start Evaporator fan will not start Condenser fan will not start Compressor runs - goes off on overload Compressor cycles on overload System runs continuously - little cooling/htg Too cool and then too warm Not cool enough on warm days Certain areas too cool, others too warm Compressor is noisy System runs - blows cold air in heating Unit will not terminate defrost Unit will not defrost Low suction pressure Low head pressure High suction pressure High head pressure
Test Method
Remedy
Pow er Failure •Test Voltage
Blow n Fuse ••• Inspect Fuse Size & Type
Unbalanced Pow er, 3PH ••• Test Voltage
Loose Connection ••• Inspect Connection - Tighten
Shorted or Broken Wires •••••• Test Circuits With Ohmmeter
Open Fan Overload •• Test Continuity of Overload
Faulty Thermostat ••• • Test Continuity of Thermostat & Wiring
Faulty Transformer •• Check Control Circuit w ith Voltmeter
Shorted or Open Capacitor ••••• Test Capacitor
Internal Compressor Overload Open •♦Test Continuity of Overload
Shorted or Grounded Compressor •• Test Motor Windings
Compressor Stuck ••• ♦Use Test Cord
Faulty Compressor Contactor ••• Test Continuity of Coil & Contacts
Faulty Fan Relay •Test Continuity of Coil And Contacts
Open Control Circuit •Test Control Circuit w ith Voltmeter
Low Voltage ••• Test Voltage
Faulty Evap. Fan Motor ••
♦Repair or Replace
Shorted or Grounded Fan Motor ••
Test Motor Windings
Improper Cooling Anticipator •• Check Resistance of Anticipator
Shortage of Refrigerant •• ♦•• Test For Leaks, Add Refrigerant
Restricted Liquid Line •• •• •
Remove Restriction, Replace Restricted Part
Open Element or Limit on Elec. Heater ♦♦ Test Heater Element and Controls
Dirty Air Filter ••• • ♦Inspect Filter-Clean or Replace
Dirty Indoor Coil ••• • ♦Inspect Coil - Clean
Not enough air across Indoor Coil ••• • ♦Check Blow er Speed, Duct Static Press, Filter
Too much air across Indoor Coil ♦•Reduce Blow er Speed
Overcharge of Refrigerant •• •♦••
Recover Part of Charge
Dirty Outdoor Coil •• • ♦•Inspect Coil - Clean
Noncondensibles ••♦•Recover Charge, Evacuate, Recharge
Recirculation of Condensing Air •• •
Remove Obstruction to Air Flow
Infiltration of Outdoor Air •••
Check Window s, Doors, Vent Fans, Etc.
Improperly Located Thermostat •• Relocate Thermostat
Air Flow Unbalanced ••
Readjust Air Volume Dampers
System Undersized •• Refigure Cooling Load
Broken Internal Parts •♦Replace Compressor
Broken Valves •• ••
Test Compressor Efficiency
Inefficient Compressor •♦•• Test Compressor Efficiency
Wrong Type Expansion Valve ••• • •• ♦Replace Valve
Expansion Device Restricted ••• • •• •
Remove Restriction or Replace Expansion Device
Oversized Expansion Valve ••
Replace Valve
Undersized Expansion Valve ••• • • Replace Valve
Expansion Valve Bulb Loose ••
Tighten Bulb Bracket
Inoperative Expansion Valve •• • Check Valve Operation
Loose Hold-dow n Bolts •Tighten Bolts
Faulty Reversing Valve •♦♦♦ ♦♦♦
Replace Valve or Solenoid
Faulty Defrost Control •♦♦♦♦♦ ♦
Test Control
Faulty Defrost Thermostat ♦♦♦♦♦♦♦
Test Defrost Thermostat
Flow rator Not Seating Properly •••
Check Flow rator & Seat or Replace Flow rator
• Cooling or Heating Cycle (Heat Pump) ♦
No Cooling Unsatisfactory
Cooling/Heating
Heating Cycle Only (Heat Pump)

14
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit3 Digit2 Digit 1
• Integrated control module
diagnostic/status LED display
shows theindicatedcode.
BLANK A 2 •Outdoorairtemp
sensor fault • Shorted sensor. • Open sensor.
• Sensor
disconnected.
•Sensoroutof
range.
•Check sensor
connection.
• Replace open/
shortedsensor.
• Turn power OFF prior to
repair.
• Replace with correct
replacement part.
• Heat pump fails to operate in
heatingmode.
• Integrated control module
diagnostic/status LED display
shows theindicatedcode.
BLANK A 3 •Outdoorcoil
tempsensorfault • Shorted sensor • Open sensor.
• Sensor.
disconnected.
•Sensoroutof
range.
•Check sensor
connection.
• Replace open/
shortedsensor.
• Turn power OFF prior to
repair.
• Replace with correct
replacement part.
• Air conditioner/heat pump
fails to operate.
• Integrated control module
diagnostic/status LED display
shows the
indicated code.
BLANK E 5 •Open fuse • Short in lowvolta
g
e
wiring. •Locateandcorrect short in lowvoltage
wiring.
• Turn power OFF prior to
repair.
• Replace fuse with
3-amp automotive type.
• Air conditioner/heat pump
fails to operate.
• Integrated control module
diagnostic/status LED display
shows the
indicated code.
BLANK E E •Boardmis-
operation • Compressor relay contacts welded. • Replace control. • Turn power OFF prior to repair
• Replace with correct
replacement part.
• Air conditioner/heat pump
fails to operate.
• Integrated control module
diagnostic/status LED display
shows theindicatedcode.
BLANK b0• Circulator
blower motor is
not running when it
should be running.
• Indoor bIower
motorproblem.
•Communications
error between
indoorandoutdoor
unit.
• Check indoor
bIower motor.
• Check indoor
bIower motor wiring.
• Check indoor unit
control.
• Repair/ replace any
faultywiring.
• Repair/ replace
indoor bIowermotor
orcontrol.
• Turn power OFF prior to
repair.
• Replace with correct
replacement part.
• Airconditioner/heat
pump operates at reduced
performance.
• Air conditioner/heat pump
operating at lowstage when
expected to operate at high
stage.
• Integrated control module
diagnostic/status LED display
shows theindicatedcode.
BLANK b9• Air flow is lower
thandemanded • Indoor bIower motorproblem
• Blocked filters .
• Restrictive/
undersized ductwork
• Indoor/outdoor
unit miss-match.
• Check indoor
blower motor.
•Check Filters
clean/replace as
needed.
•Check ductwork,
resize as needed.
• Verifyindoor and
outdoorunitsare
properlymatched.
• Turn power OFF prior to
repair.
• Replace with correct
replacement part.See speci
cation sheet s for airow re
uirements and ma imum e
ter nal static pressure.
• See specification sheets
for approved
system matches.
SYSTEM TROUBLESHOOTING
UNITARY DIAGNOSTIC CODES
Symptoms of Abnormal
Operation
(Legacy & ComfortNet™
Thermostat)
Diagnostic/Status
LED DisplayCodes Fault
Description Possible Causes Corrective Actions Notes &
Cautions

15
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
• Air conditioner/heat pump fails
to operate.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK d 0 •Datanot yeton
Network • Air conditioner/ heat pump is wired
as part of a
communicating
system and
integrated control
module does
not contain any
shared data.
•Verifysystem type
(communicating or
legacy)
• Populate shared data
usingmemorycard
•Wiresystem as
legacysystem
• Turn power OFF prior to
repair.
• Use memorycard for your
specific model.
• Insert memorycard
BEFORE turningpower ON.
Memorycard mayberemoved
after data is loaded.Turn
power OFF before removing
memorycard.
• Error code will be cleared
once data is loaded.
• Air conditioner/heat pump fails
to operate.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK d 1 • Invalid Data on
Network • Air conditioner/ heat pump is wired
as part of a
communicating
system and
integrated control
module contains
invalid shared data
or network data is
invalid for
the integrated
control module.
• Verify system type
(communicating or
legacy).
• Populate correct
shared data using
memorycard.
•Wiresystem as
legacysystem.
• Turn power OFF prior to
repair.
• Use memorycard for your
specific model.
• Insert memorycard
BEFORE turningpower ON.
Memorycard mayberemoved
after data is loaded.Turn
power OFF before removing
memorycard.
• Error code will be cleared
once data is loaded.
• Air conditioner/heat pump fails
to operate.
• Air conditioner/heat pump
operating at reduced
performance.
• Air conditioner/heat pump
operating at lowstage when e
peeled to operate at high stage.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK d 2 •System
Mis-Match • Airconditioner/ heat pump is wired
as part of a
communicating
system and
outdoorunit
requires air flow
greater than indoor
units
airflow capability.
• Shared data is
incompatiblewith
the system or
missing
parameters.
•Verifysystem type
(communicating or
legacy).
•Verifyshareddatais
correctforyour
specific model
repopulatedataif
required.
•Wiresystem as
legacysystem.
• Turn power OFF prior to
repair.
• Use memorycard for your
specific model.
• Insert memorycard
BEFORE turningpower ON.
Memorycard mayberemoved
after data is loaded.Turn
power OFF before removing
memorycard.
• Error code will be cleared
once data is loaded.
UNITARY DIAGNOSTIC CODES
Diagnostic/Status
LED DisplayCodes Possible
Causes Corrective Actions Notes & Cautions
Symptoms of
Abnormal Operation
(Legacy & ComfortNet™
Thermostat) Digit3 Digit2 Digit 1
Fault
Description

16
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit 3 Digit 2 Digit 1
• Air conditioner/heat pump
fails to operate.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK d 3 • Configuration
Mis-match • Shared data sent to integrated
control module
does not match
hardware
configuration.
• Verifysystem
type
(communicating
orlegacy).
• Verifyshared
data is correct for
your specific
model;re-
populate data if
required.
• Wire system as
legacysystem.
• Turn power OFF
prior to repair.
•Usememorycardfor
your specific model.
• Insert memorycard
BEFOREturning
power ON. Memory
card may be removed
after data is loaded.
Turn power OFF
before removing
memorycard.
• Error code will be
cleared once data is
loaded.
• Air conditioner/heat pump
fails to operate.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK d 4 • InvalidMemory
CardData • Shared data on memorycardhas
been rejected.
• Verifysystem
type
(communicating
orlegacy).
• Verifyshared
data is correct for
your specific
model;re-
populate data if
required.
• Wire system as
legacysystem.
• Turn power OFF
prior to repair.
•Usememorycardfor
your specific model.
• Insert memorycard
BEFOREturning
power ON. Memory
card may be removed
after data is loaded.
Turn power OFF
before removing
memorycard.
• Error code will be
cleared once data is
loaded.
• Very long run time.
• Four consecutive
compressorprotector trips with
average run time between trips
greater than 3 hours.
• Compressor operating at high
speed and outdoor fan
operating at lowspeed
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 1 •LowSide Fault •Lowrefrigerant
charge.
• Restrictionin
liquid line.
• Indoor blower
motor failure.
• Indoor
thermostat set
extremelylow.
• Verifyrefrigerant
charge;adjust as
needed.
•Check for
restricted liquid
line;repair/
replace as
needed.
• Check indoor
blower motor;
repair/replace as
needed.
•Check indoor
thermostat
setting.
• Turn power OFF
prior to repair.
• Fault will clear after
3 consecutive normal
cycles.
• Fault maybe cleared
bycycling 4V AC to
control.
• Replace with correct
replacement part(s).
•Compressorandoutdoorfan
are off.
• Thermostat demand is
present.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 1 •Low ressureCut
Out Trip •Lowrefrigerant charge.
• Restrictionin
liquid line.
• Indoor blower
motor failure.
•Indoor
thermostat set
extremelylow.
• Verifyrefrigerant
charge;adjust as
needed.
•Check for
restricted liquid
line;repair/
replace as
needed.
• Check indoor
blower motor;
repair/replace as
needed.
•Check low
pressure switch;
repair/replace as
needed.
•Check indoor
thermostat
setting.
• Turn power OFF
prior to repair.
• Replace with correct
replacement part(s).
UNITARY DIAGNOSTIC CODES
Symptoms of Abnormal
Operation
(Legacy & ComfortNet™
Thermostat)
Diagnostic/Status
LED Displav Codes Fault
Description Possible Causes Corrective Actions Notes & Cautions

17
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit3 Digit2 Digit 1
• Compressor and outdoor fan are
off.
• Lowpressureswitchtrip3times
within same thermostat demand.
• Thermostat demand is present.
• Intergrated control module
diagnostic/status LED display
shows the indicated code.
BLANK L 1 • LowPressureCut
Out Lockout (3Trips) • Lowrefrigerant charge.
• Restriction in
liquid line.
• Indoor blower
motorfailure.
• Indoor
thermostat set
extremelylow.
• Verifyrefrigerant
charge;adjust as
needed.
• Check for
restricted liquid
line;repair/replace
as needed.
• Check indoor
blower motor;
repair/replace as
needed.
• Check low
pressureswitch;
repair/replace as
needed.
• Check indoor
thermostat setting.
• Turn power OFF prior
to repair.
• Must clearfault by
cycling 24 VAC to
control.
• Replace with correct
replacement part(s).
• Four consecutive compressor
protector trips with average run
time between trips greater than 1
minute and less than 15 minutes.
• Lowpressure and high pressure
switches are closed.
• Intergrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 2 • High Side Fault • Blocked
condenser coil.
• Outdoor fan not
running.
• Check and clean
condenser coil.
•Check outdoor
fanmotor;
repair/replace as
needed.
•Check outdoor
fanmotorwiring;
repair/replace as
needed.
•Check outdoor
fanmotor
capacitor;replace
as needed.
• Turn power OFF prior
to repair.
• Fault will clear after 4
consecutive normal
cycles.
• Fault maybe cleared
bycycling 24 VAC to
control.
• Replace with correct
replacement part(s)
• Compressor and outdoor fan are
off.
• Thermostat demand is present.
• Intergrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 2 •HighPressureCut
Out Trip • Blocked condenser coil.
• Outdoor fan not
running.
• Check and clean
condenser coil.
•Check outdoor
fanmotor;
repair/replace as
needed.
•Check outdoor
fanmotorwiring;
repair/replace as
needed.
•Check outdoor
fanmotor
capacitor;replace
as needed.
• Turn power OFF prior
to repair.
• Replace with correct
replacement part(s).
• Compressor and outdoor fan
are off.
•Lowpressureswitchtrip3times
within same thermostat demand.
• Thermostat demand is present.
• Intergrated control module
diagnostic/status LED display
shows the indicated code.
BLANK L 2 •HighPressureCut
Out Lockout (3Trips) • Blocked condenser coil.
• Outdoor fan not
running.
• Check and clean
condenser coil.
•Check outdoor
fanmotor;
repair/replace as
needed.
•Check outdoor
fanmotorwiring;
repair/replace as
needed.
•Check outdoor
fanmotor
capacitor;replace
as needed.
•Turn power OFF prior
to repair.
•Must clear fault by
cycling 24 VAC to
control.
•Replace with correct
replacement part(s).
Symptoms of Abnormal
Operation (Legacy &
ComfortNet™
Thermostat)
Fault
Description Possible Causes Corrective Actions Notes & Cautions
UNITARY DIAGNOSTIC CODES
Diagnostic/Status
LEDDisplay Codes

18
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit3 Digit2 Digit 1
• Run time for last 4 cycles is
less than 3 minutes each.
• Compressor protector has not
tripped.
• Low pressure and high
pressure switches are closed.
• Integrated control module
diagnostic/status LED <lisp!ay
sho ws the indicated code .
BLANK 0 3 • Short Cycling • Intermittent
thermostat
demand.
• Faulty
compressorrelay.
• Check
thermostat and
thermostat wiring;
repair/ replace as
needed.
•Check
compressorrelay
operation;replace
control as needed.
•Turnpower OFF
prior to repair.
• Fault will clear
after 4 consecutive
normal cycles.
• Fault may be
cleared bycycling
24VAC to control.
• Replace with
correct
replacement
part(s).
• Minimum
compressor run
time is changed
from 30 seconds
to 3 minutes.
• Compressor and outdoor fun
are off.
•Compressorprotectortrips
four consecutive times.
• Average run time between trips
is less than 15seconds.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 4 •LockedRotor • Compressor
bearings are
seized.
• Failed
compressor run
capacitor.
• Faultyrun
capacitor wiring.
• Lowline voltage.
•Check
compressor
operation; repair/
replace as needed.
• Check run
capacitor;replace
as needed.
• Check wiring;
repair/replace as
needed.
• Verifyline voltage
is within range on
rating plate;
contact local utility
is out of range.
•Turnpower OFF
prior to repair.
• Must clear fault
bycycling 24V AC
to control.
• Replace with
correct
replacement
part(s).
• Compressor and outdoor fun
are off for greater than 4 hours.
• Low pressure and high
pressure switches are closed.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 0 5 • Open Circuit • Power is
disconnected.
• Failed
compressor
protector.
• Compressornot
properlywired to
control.
• Check circuit
break ers and
fuses .
• Check wiring to
unit; repair/ replace
as needed.
•Check
compressor
repair/replace as
needed
•Check
compressorwiring;
repair/ replace as
needed.
• Turn power OFF
prior to repair.
• Fault will clear
after 1normal
cycle.
• Fault may be
cleared bycycling
24V AC to control.
• Replace with
correct
replacement
part(s).
• Compressor and outdoor fun
are off.
• Low pressure and high
pressure switches are closed.
• Integrated control module
diagnostic/status LED display
shows the indicated code.
BLANK 06•OpenStart
Circuit • Compressor start winding is
open.
• Failed
compressor run
capacitor.
• Faultyrun
capacitor wiring.
• Compressornot
properlywired to
control.
• Faulty
compressor wiring.
•Check
compressor
repair/replace as
needed.
• Check run
capacitor;replace
as needed.
•Check wiring;
repair/replace as
needed.
•Turnpower OFF
prior to repair.
• Fault will clear
after 1normal
cycle.
• Fault may be
cleared bycycling
24V AC to control.
• Replace will
correct
replacement
part(s).
UNITARY DIAGNOSTIC CODES
Symptoms of
Abnormal Operation
(Legacy & ComfortNet™
Thermostat)
Diagnostic/Status
LEDDisplay Codes Fault
Description Possible Causes Corrective Actions Notes &
Cautions

19
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit 3 Digit 2 Digit 1
• Compressor and outdoor fan are off.
• Low pressure and hi
g
h pressure switches
are closed.
•Openstart circuit has been detected 4
times within 5 minute delay between each
detection.
•Integrated control module
diagnostic/status LED displayshows the
indicated code.
BLANK L 6 •OpenStart
Circuit Lockout • Compressor start winding is
open
• Failed
compressorrun
capacitor.
• Faultyrun
capacitorwiring.
• Compressor
not properly
wired to control.
• Faulty
compressor
wiring.
• Check
compressor;
repair/replace as
needed.
• Check run
capacitor; replace
as needed.
• Check wiring
repair/replaced as
needed.
• Turn power OFF
prior to repair.
•Must clearfault
b
y
c
y
clin
g
24 VAC
to control.
•Replace with
correct
replacement
part(s).
• Compressor and outdoor fan are off.
• Low pressure and hi
g
h pressure switches
are closed.
•Integrated control module
diagnostic/status LED displayshows the
indicated code.
BLANK 0 7 •OpenRunCircuit •Compressor
run winding is
open
• Compressor
not properly
wired to control.
• Faulty
capacitorwiring.
• Check
compressor;
repair/replace as
needed.
• Check wiring
repair/replaced as
needed.
• Turn power OFF
prior to repair.
• Fault will clear
after 1normal
cycle.
• Fault maybe
c
y
clin
g
24 VAC to
control.
•Replace with
correct
replacement
part(s).
• Compressor and outdoor fan are off.
• Low pressure and hi
g
h pressure switches
are closed.
•Openstart circuit has been detected 4
times within 5 minute delay between each
detection.
•Integrated control module
diagnostic/status LED displayshows the
indicated code.
BLANK L 7 •OpenRunCircuit
Lockout • Compressor run winding is
open
• Compressor
not properly
wired to control.
• Faulty
capacitorwiring.
• Check
compressor;
repair/replace as
needed.
• Check wiring
repair/replaced as
needed.
• Turn power OFF
prior to repair.
•Must clearfault
b
y
c
y
clin
g
24 VAC
to control.
•Replace with
correct
replacement
part(s).
•Air conditioner/heat pump ma
y
appear to
be operating normally.
• Compressor protecor may be open
(compressor and outdoor fan off).
•Integrated control module
diagnostic/status LED displayshows the
indicated code.
BLANK L 8 • LowLine Voltage • Lowline
voltage. •Check circuit breakers and fuses.
•Verifyunit is
connected to power
supplyas specified
on rating plate.
• Correct lowline
voltage condition;
contact localutility
if needed.
• Turn power OFF
prior to repair.
• Control detects
line voltage less
than185VAC.
•Fault willclearif
linevoltage
increases above
18 5 V A C .
Notes &
Cautions
UNITARY DIAGNOSTIC CODES
Diagnostic/Status
LED DisplayCodesSymptoms of Abnormal
Operation (Legacy &
ComfortNet™ Thermostat)
Fault
Description Possible Causes Corrective Actions

20
TROUBLESHOOTING INFORMATION: UNITARY DIAGNOSTIC CODES
Digit 3 Digit 2 Digit 1
• Air conditioner/heat
pump may appear to be
operating normally.
•Compressorprotecor
maybe open (compressor
and outdoor fan off).
•Integrated control
module diagnostic/status
LED displayshows the
indicatedcode.
BLANK H 8 • High Line
Voltage • High line voltage • Correct high line voltage condition;
contact local utility
if needed.
• Verifyunit is
connected to
power supplyas
specified on rating
plate.
•TurnpowerOFF
prior to repair.
• Control detects
line voltage greater
than 255 VAC.
• Fault will clear if
line voltage
decreases below
255 VAC.
• Air conditioner/heat
pump may appear to be
operating normally.
•Integrated control
module diagnostic/status
LED displayshows the
indicatedcode.
BLANK 0 9 •LowPilot
Voltage •Controldetects secondary
voltage less than
18 V A C .
• Transformer
overloaded.
• Lowline voltage.
•Check fuse.
•Correct low
secondary voltage
condition.
• Check
transformer;
replace if needed.
•TurnpowerOFF
prior to repair.
• Fault will clear if
secondary voltage
rises above 21VAC.
• Replace with
correct
replacement part(s).
• Compressor is off.
•Integrated control
module diagnostic/status
LED displayshows the
indicatedcode.
BLANK P 0 •Comp
protector Open • No current through run or
start windings.
• Compressor run
winding is open.
• Compressor
not properlywired
to control.
•Faulty
Compressor
wiring.
• Failed
compressorrun
capacitor.
•Faultyrun
capacitorwiring.
• Check
compressor;
repair/replace as
needed.
• Check wiring
repair/replaced as
needed.
• Check run
capacitor;replace
as needed.
•TurnpowerOFF
prior to repair.
• Fault will clear
after1normal cycle.
• Must clear fault by
cycling 24 VAC to
control.
• Replace with
correct
replacement part(s).
• Air conditioner/heat
pump may appear to be
operating normally.
•Compressorprotecor
maybe open (compressor
and outdoor fan off).
•Integrated control
module diagnostic/status
LED displayshows the
indicatedcode.
BLANK L 8 • LowLine
Voltage • Lowline voltage. • Check circuit breakers and
fuses.
• Verifyunit is
connected to
power supplyas
specified on rating
plate.
• Correct lowline
voltage condition;
contact local utility
if needed.
•TurnpowerOFF
prior to repair.
• Control detects
line voltage less
than185VAC.
• Fault will clear if
line voltage
increases above
18 5 V A C .
• Air conditioner/heat
pump may appear to be
operating normally.
•Compressorprotecor
maybe open (compressor
and outdoor fan off).
•Integrated control
module diagnostic/status
LED displayshows the
indicatedcode.
BLANK L 8 • No Line
Voltage • No line voltage. • Check circuit breakers and
fuses.
• Verifyunit is
connected to
power supplyas
specified on rating
plate.
•TurnpowerOFF
prior to repair.
• Control detects
line voltage less
than185VAC.
• Fault will clear if
line voltage
increases above
18 5 V A C .
UNITARY DIAGNOSTIC CODES
Symptoms of
Abnormal Operation
(Legacy &
ComfortNet™
Thermostat)
Diagnostic/Status
LED DisplayCodes Fault
Description Possible Causes Corrective Actions Notes & Cautions