Daikin DZ20VC Series Operating instructions

©2014-2017, 2020
RSD6215002r8
September 2020
DZ20VC Inverter Heat Pump Condenser Units
with R-410A Refrigerant
Blowers, Coils, & Accessories
Service Instructions
O NLY PERSONNEL THAT HAVE BEEN TRAINED TO INSTALL , ADJUST , SERVICE OR
REPAIR ( HEREINAFTER , “ SERVICE ”) THE EQUIPMENT SPECIFIED IN THIS
MANUAL SHOULD SERVICE THE EQUIPMENT . T HE MANUFACTURER WILL NOT
BE RESPONSIBLE FOR ANY INJURY OR PROPERTY DAMAGE ARISING FROM
IMPROPER SERVICE OR SERVICE PROCEDURES . I F YOU SERVICE THIS UNIT , YOU
ASSUME RESPONSIBILITY FOR ANY INJURY OR PROPERTY DAMAGE WHICH MAY
RESULT . I N ADDITION , IN JURISDICTIONS THAT REQUIRE ONE OR MORE
LICENSES TO SERVICE THE EQUIPMENT SPECIFIED IN THIS MANUAL , ONLY
LICENSED PERSONNEL SHOULD SERVICE THE EQUIPMENT . I MPROPER
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 .
Cancer and Reproductive Harm -
www.P65Warnings.ca.gov
PROP 65 WARNING
FOR CALIFORNIA CONSUMERS
0140M00517-A
WARNING

IMPORTANT INFORMATION
2
SAFE REFRIGERANT HANDLING
While these items will not cover every conceivable situation, they
should serve as a useful guide.
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
IMPORTANT NOTICES FOR CONSUMERS
AND SERVICERS
RECOGNIZE SAFETY SYMBOLS, WORDS AND LABELS
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
T O PREVENT THE RISK OF PROPERTY DAMAGE , PERSONAL INJURY , OR
DEATH , DO NOT STORE COMBUSTIBLE MATERIALS OR USE GASOLINE OR
OTHER FLAMMABLE LIQUIDS OR VAPORS IN THE VICINITY OF THIS
APPLIANCE .
WARNING
Pride and workmanship go into every product to provide our
customers with quality products. It is possible, however, that
during its lifetime a product may require service. Products
should be serviced only by a qualified service technician who
is familiar with the safety procedures required in the repair and
who is equipped with the proper tools, parts, testing instru-
ments and the appropriate service manual. REVIEW ALL SERVICE
INFORMATION IN THE APPROPRIATE SERVICE MANUAL BEFORE
BEGINNING REPAIRS.
To locate an authorized servicer, please consult your
telephone book or the dealer from whom you purchased this
product. For further assistance, please contact:
CONSUMER INFORMATION LINE - DAIKIN BRAND PRODUCTS
TOLL FREE 1-855-770-5678 (U.S. only)
email us at: [email protected]
fax us at: [phone]
(Not a technical assistance line for dealers.)
Outside the U.S., call 1-713-861-2500.
(Not a technical assistance line for dealers.)
our telephone company will bill you for the call.
IMPORTANT INFORMATION ............................................... 2 - 3
PRODUCT IDENTIFICATION ................................................... 4
ACCESSORIES ................................................................... 5 - 6
TESTING CAPACITOR RESISTANCE ............................... 7 - 8
REPLACING THE CONTROL BOARD ..................................... 9
SYSTEM OPERATION ..................................................... 10 - 16
COOLING ANALYSIS CHART ................................................ 17
HEATING ANALYSIS CHART ................................................. 18
SERVICING TABLE OF CONTENTS ...................................... 19
SERVICING ..................................................................... 20 - 59
TROUBLESHOOTING - INDOOR UNIT .................. 39 - 54
EMERGENCY MODE ............................................... 55 - 59
SETTING THE MODE DISPLAY- OUTDOOR UNIT ........ 60 - 65
7-SEGMENT DISPLAY- OUTDOOR UNIT ...................... 66 - 68
TROUBLESHOOTING - OUTDOOR UNIT ...................... 69 - 75
THERMISTOR RESISTANCE
& TEMPERATURE CHARACTERISTICS ....................... 76
PRESSURE VS TEMPERATURE CHART ............................. 77
LIQUID LINE TEMPERATURE CHART ................................. 78
WIRING DIAGRAM ...........................................................79 - 82
CTK04 ADDENDUM ..................................................... 83 - 112
I NVERTER H/P MODELS CAN ONLY BE MATCHED WITH A DV**PEC AIR
H ANDLER , TXV-V** EXPANSION VALVE KIT . D AMAGE RESULTING
FROM OPERATION WITH ANY OTHER COMBINATION IS NOT COVERED BY
OUR WARRANTIES . DV**PEC AIR HANDLER IS APPLICABLE ONLY FOR
DZ20VC0**1BA
MODEL OR LATER REVISION .
NOTICE
D O NOT CONNECT TO OR USE ANY DEVICE THAT IS NOT DESIGN
CERTIFIED BY THE MANUFACTURER FOR USE WITH THIS UNIT . S ERIOUS
PROPERTY DAMAGE , PERSONAL INJURY , REDUCED UNIT PERFORMANCE
AND / OR HAZARDOUS CONDITIONS MAY RESULT FROM THE USE OF
SUCH NON - APPROVED DEVICES .
WARNING

IMPORTANT INFORMATION
3
S YSTEM CONTAMINANTS , IMPROPER SERVICE PROCEDURE AND / OR
PHYSICAL ABUSE AFFECTING HERMETIC COMPRESSOR ELECTRICAL
TERMINALS MAY CAUSE DANGEROUS SYSTEM VENTING .
WARNING
NOTICE:
WHEN THE OUTDOOR UNIT IS CONNECTED TO MAIN POWER, THE
INVERTER BOARD HAS ASMALL CURRENT FLOWING INTO IT TO BE
PREPARED FOR OPERATION WHEN NEEDED. DUE TO THIS, THE CON-
TROL BOARD COMPONENTS HAVE TO BE COOLED EVEN WHEN THE UNIT
IS NOT RUNNING. FOR THIS COOLING OPERATION, THE CONDENSER FAN
MAY COME ON AT ANY TIME, INCLUDING IN THE WINTER MONTHS. ANY
OBSTRUCTION TO THE OUTDOOR FAN SHOULD BE AVOIDED AT ALL TIMES
WHEN THE UNIT IS POWERED TO PREVENT DAMAGE.
The successful development of hermetically sealed refrigeration
compressors has completely sealed the compressor's moving parts
and electric motor inside a common housing, minimizing refriger-
ant leaks and the hazards sometimes associated with moving belts,
pulleys or couplings.
Fundamental to the design of hermetic compressors is a method
whereby electrical current is transmitted to the compressor mo-
tor through terminal conductors which pass through the com-
pressor housing wall. These terminals are sealed in a dielectric
material which insulates them from the housing and maintains
the pressure tight integrity of the hermetic compressor. The termi-
nals and their dielectric embedment are strongly constructed, but
are vulnerable to careless compressor installation or mainte-
nance procedures and equally vulnerable to internal electrical
short circuits caused by excessive system contaminants.
In either of these instances, an electrical short between the termi-
nal and the compressor housing may result in the loss of integrity
between the terminal and its dielectric embedment. This loss may
cause the terminals to be expelled, thereby venting the vaporous
and liquid contents of the compressor housing and system.
A venting compressor terminal normally presents no danger to
anyone, providing the terminal protective cover is properly in
place.
If, however, the terminal protective cover is not properly in place,
a venting terminal may discharge a combination of
(a) hot lubricating oil and refrigerant
(b) flammable mixture (if system is contaminated
with air)
in a stream of spray which may be dangerous to anyone in the
vicinity. Death or serious bodily injury could occur.
Under no circumstances is a hermetic compressor to be electri-
cally energized and/or operated without having the terminal pro-
tective cover properly in place.
See Service Section S-17 for proper servicing.
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-410A TO A RETURNABLE
R-410A CYLINDER . T HE SERVICE EQUIPMENT USED MUST BE LISTED
OR CERTIFIED FOR THE TYPE OF REFRIGERANT USE .
•S
TORE CYLINDERS IN A COOL , DRY PLACE . N EVER USE A CYLINDER
AS
A PLATFORM OR A ROLLER .
WARNING
T O AVOID POSSIBLE EXPLOSION :
•U
SE 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 LBS .
W
HEN IN DOUBT , DO NOT USE THE CYLINDER .
WARNING
T HE U NITED S TATES E NVIRONMENTAL P ROTECTION A GENCY (”EPA”)
HAS ISSUED VARIOUS REGULATIONS REGARDING THE INTRODUCTION
AND DISPOSAL OF REFRIGERANTS INTRODUCED INTO THIS UNIT .
F
AILURE TO FOLLOW THESE REGULATIONS MAY HARM THE
ENVIRONMENT AND CAN LEAD TO THE IMPOSITION OF SUBSTANTIAL
FINES . T HESE REGULATIONS MAY VARY BY JURISDICTION . S HOULD
QUESTIONS ARISE , CONTACT YOUR LOCAL EPA OFFICE .
WARNING
T O AVOID POSSIBLE INJURY , EXPLOSION OR DEATH , PRACTICE SAFE
HANDLING OF REFRIGERANTS .
WARNING
T HE COMPRESSOR PVE 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
NLY USE AIKIN APPROVED COMMUNICATING THERMOSTATS
PPROVED COMMUNICATING THERMOSTATS ARE
SMARTTHERMOSTATAND ORNEWER EREINAFTER
REFFERED TO AS HERMOSTAT
O D .
A DAIKIN ONE+
CTK04AE . (H
“T ”)
NOTICE
HE ENTIRE SYSTEM COMBINATION OF INDOOR AND OUTDOOR
SECTIONS MUST BE MANUFACTURER APPROVED AND
IR ONDITIONING EATING AND EFRIGERATION NSTITUTE
LISTED NSTALLATION OF UNMATCHED SYSTEMS IS NOT
PERMITTED AMAGE OR REPAIRS DUE TO INSTALLATION OF
UNMATCHED SYSTEM IS NOT COVERED UNDER THE WARRANTY
T (
)
A-C ,H , R I (AHRI)
. NOTE: I
. D
.
NOTICE

PRODUCT IDENTIFICATION
4
NOMENCLATURES
D V 24 P E C C 1 A AA
1 2 3,4 5 678 9 10 11,12
Brand Engineering*
D - Daikin Single-Piece Major & Minor revisions
Air Handler
*Not used for inventory management
Refrigerant Compatability
4 - R-410A
Variable-Speed Motor
Electric
Normal Capacity Range 1 - 208/230 V, 1 Phase 60 Hz
25 - 2 Tons 59 - 4 Tons
37 - 3 Tons 61 - 5 Tons Cabinet Width
B - 17‰" C - 21"
D - 24‰"
F- Fit
P - Non-Fit C - Yes
Expansion Device
E - Electronic Expansion Valve
T - Thermal Expansion Valve
D Z 20 V C 036 3 * *
1 2 3,4 5 6 7,8,9 10 11 12
Brand Engineering *
D - Daikin Major & Minor revisions
* Not used for inventory purposes
Type Voltage
X - AC R-410A 1 - 208/230 V Single-Phase 60 Hz
Z - HP R-410A
Capacity
SEER 024 - 2 tons 048 - 4 tons
14 - 14 SEER 18 - 18 SEER 036 - 3 tons 060 - 5 tons
16 - 16 SEER 20 - 20 SEER
Feature Set
Compressor A - Base D - Deluxe
S - Single Stage V - Variable Speed C - ComfortNet 4-Wire Ready N - Nominal
T - Two Stage

ACCESSORIES
5
SS = 2°C (3.6°F) or according
to customer specication
Number of turns
from SS to
tight spring
Number of turns
from SS to
loose spring
R22 +7.25 –4.25
R410A +9.5 –2
R410A: 0.6°C / turn - 1.1°F /
R410A - Max. 75°C (167°F)
Number of turns Number of turns
from SS to from SS to
TIGHT Spring LOOSE Spring
R410A +9.5 -2

-

+
EXPANSION VALVES
Model Name TXV-Kit
DZ20VC0241** TXV-V24
DZ20VC0361** TXV-V36
DZ20VC0481** TXV-V48
DZ20VC0601** TXV-V60
DZ20VC***1**

6
MODELS
HKSX03XC HKSX05XC HKSX06XC HKSX08XC HKSX10XC HKSC05XC HKSC08XC HKSC10XC
HKSC15XA
HKSC15XB
HKSC15XF
HKSC19CA HKSC19CB
HKSC20DH HKSC20DB
HKSC20XF
HKSC25DA HKSC25DB
DV25PECB14A*
XXXXXXXX
DV37PECC14A*
XXXXXXXXXXXX
DV59PECD14A*
XXXXXXX XX XX
DV61PECD14A*
XXXXXXX XX XXXXX
*Revision level that may or may not be designated.
NOTE: Airflow selection should meet the minimum requirements as mentioned in the air handler installation instructions.
ACCESSORIES
NOTE: For emergency mode heating, set the dipswitch on Control Board. For heating mode, use the thermostat user
menu.
For heater kit installation, it is important to set the capacity of the electric heater at Set-up menu on thermostat and DIP switch on
indoor unit control board. For more information, please see indoor unit I/O manual.
Heater Kit
Selection DV25PECB14A* DV37PECC14A*+ DV59PECD14A*++ DV61PECD14A* S-9 S-10 S-11 S-12
Noheater----OFFOFFOFFOFF
First 3 5 5 5 ON ON ON ON
Second5666ONONONOFF
Third 6 8 8 8 ON ON OFF ON
Fourth 8 10 10 10 ON ON OFF OFF
Fifth10151515ONOFFONON
Sixth X 19 20 20 ON OFF ON OFF
Seventh X X X 25 ON OFF OFF ON
VALID SWITCH SETTINGS
Heater kW Dip Switch Setting IndoorControl Board DS Bank 3
+For match up with a 2 ton outdoor unit: Heater kit application shall not exceed 10 kW.
++For match up with a 3 ton outdoor unit: Heater kit application shall not exceed 15 kW.
HEATER KIT
Condensate Management Kits*
CMK0008 CMK0009 CMK0010 CMK0011
DV25PECB14** DV37PECC14** DV59PECD14** DV61PECD14**
DFK-B DFK-C DFK-D
DV25PECB14** DV37PECC14** DV59PECD14**
DV61PECD14**
DV**PEC

7
TESTING CAPACITOR RESISTANCE
DZ20VC0241**
A VOID CONTACT WITH THE CHARGED AREA .
•N
EVER TOUCH THE CHARGED AREA BEFORE CONFIRMING THAT THE RESIDUAL VOLTAGE IS 50 VOLTS OR LESS .
1. S
HUT DOWN THE POWER AND LEAVE THE CONTROL BOX FOR 10 MINUTES .
2. M
AKE SURE TO TOUCH THE E ARTH GROUND TERMINAL TO RELEASE THE STATIC ELECTRICITY FROM YOUR BODY ( TO PREVENT
FAILURE OF THE PC BOARD ).
3. M
EASURE THE RESIDUAL VOLTAGE IN THE SPECIFIED MEASUREMENT POSITION USING A VOM WHILE PAYING ATTENTION NOT TO
TOUCH THE CHARGED AREA .
4. I
MMEDIATELY AFTER MEASURING THE RESIDUAL VOLTAGE , DISCONNECT THE CONNECTORS OF THE OUTDOOR UNIT ’ S FAN
MOTOR . (I F THE FAN BLADE ROTATES BY STRONG WIND BLOWING AGAINST IT , THE CAPACITOR WILL BE CHARGED, CAUSING
THE DANGER OF ELECTRICAL SHOCK .)
WARNING
Capacitor Voltage

8
A VOID CONTACT WITH THE CHARGED AREA .
•N
EVER TOUCH THE CHARGED AREA BEFORE CONFIRMING THAT THE RESIDUAL VOLTAGE IS 50 VOLTS OR LESS .
1. S
HUT DOWN THE POWER AND LEAVE THE CONTROL BOX FOR 10 MINUTES .
2. M
AKE SURE TO TOUCH THE E ARTH GROUND TERMINAL TO RELEASE THE STATIC ELECTRICITY FROM YOUR BODY ( TO PREVENT
FAILURE OF THE PC BOARD ).
3. M
EASURE THE RESIDUAL VOLTAGE IN THE SPECIFIED MEASUREMENT POSITION USING A VOM WHILE PAYING ATTENTION NOT TO
TOUCH THE CHARGED AREA .
4. I
MMEDIATELY AFTER MEASURING THE RESIDUAL VOLTAGE , DISCONNECT THE CONNECTORS OF THE OUTDOOR UNIT ’ S FAN
MOTOR . (I F THE FAN BLADE ROTATES BY STRONG WIND BLOWING AGAINST IT , THE CAPACITOR WILL BE CHARGED, CAUSING
THE DANGER OF ELECTRICAL SHOCK .)
WARNING
C+ C-
Capacitor Voltage
DZ20VC0361**
DZ20VC0481**
DZ20VC0601C* (or later)
TESTING CAPACITOR RESISTANCE
HE PECIFICATION OF OR EARLIER MODELS ARE
DIFFERENT FROM THIS SPECIFICATION
OR DETAILS SEE THE SERVICE MANUAL THAT MATCHES THE MAJOR
REVISION OF MODEL NAME
T S DZ20VC0601B
.
F ,
.
NOTICE

9
REPLACING THE CONTROL BOARD
HIGH VOLTAGE !
D ISCONNECT ALL POWER BEFORE SERVICING OR
INSTALLING . M ULTIPLE POWER SOURCES MAY BE
PRESENT . F AILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE , PERSONAL INJURY OR DEATH .
WARNING
W HEN REPLACING THE CONTROL BOARD , DO NOT TOUCH THE
HATCHED AREAS . B EFORE INSTALLING THE NEW CONTROL BOARD , BE
SURE TO WIPE THE GREASE OFF THE REFRIGERANT TUBING . E XERCISE
CAUTION TO NOT DAMAGE THE ELECTRICAL CONNECTIONS .
D
ISCONNECT AS NEEDED .
CAUTION
HE PECIFICATION OF OR EARLIER MODELS ARE
DIFFERENT FROM THIS SPECIFICATION
OR DETAILS SEE THE SERVICE MANUAL THAT MATCHES THE MAJOR
REVISION OF MODEL NAME
T S DZ20VC0601B*
.
F ,
.
NOTICE
Uninstall the control board
When uninstalling the main control board, remove the screws
holding the cover in place. If board replacement is attempted
without following proper uninstallation procedure, the refriger-
ant piping might be damaged. Always replace the grease with new
grease on heat sink used for cooling. Not replacing grease may
result in insufficient cooling and may damage the control board.
1. Remove the fixing screw A.
2. Lift the cover and open it in the direction shown in the figure.
3. Remove fixing screws B affixing the sheet metal plate.
4. Carefully slide the sheet metal plate with the control board
behind the refrigerant tubing as shown.
Install the control board
When working on a service port, ensure that no refrigerant and/or
compressor oil is sprayed onto the control board. This could dam-
age the board’s functionality.
1. Wipe the stale grease completely from the installed piping. If
you reinstall the control board, make sure to wipe clean the
heat sink on the board. Coat the surface with the standard
quantity of the specified new grease.
2. Carefully slide the sheet metal plate back in and fix the screws
B.
3. Do not apply force to the parts on the control board. Hold the
control board plate NOT the control board.
4. Ensure that the liquid tube does not come in contact with any
part of the control board assembly.
5. Gently fit the tube in the heat sink troughs. Ensure good con-
tact.
6. Close the cover, slide it downwards, fix it with the nails (two
nails) and tighten fixing screws A so that the piping is tightly
connected.
Fixing
screwA
Cover
RefrigerantTubing
Heatsinkforcooling
fixingscrewsB
Use the grease that
is provided with the
service parts
.20
.20
Make sure
that you are
coating
evenly
Tightening Torque:
14.1±1.7 lbf-in
Tighten with a driver
until the position where a
tightening torque increases
suddenly.
Then extra-tighten by 30°
to 40º.
Screw
A
Nail
Nail

SYSTEM OPERATION
10
This section gives a basic description of heat pump condenser
unit operation, its various components and their basic opera-
tion. Ensure your system is properly sized for heat gain and loss
according to methods of the Air Conditioning Contractors Asso-
ciation (ACCA) or equivalent.
CONDENSING UNIT
The ambient air is pulled through the heat pump condenser coil
by a direct drive propeller fan. This air is then discharged out of
the top of the cabinet. These units are designed for free air dis-
charge, so no additional resistance, like duct work, shall be at-
tached.
The gas and liquid line connections on present models are of the
sweat type for field piping with refrigerant type copper. Front
seating valves are factory installed to accept the field run copper.
The total refrigerant charge for a normal installation is factory
installed in the heat pump condenser unit.
DZ20VC models are available in 2 through 5 ton sizes and use R-
410A refrigerant. They are designed for 208/230 volt single phase
applications.
DZ20VC R-410A model units use a Daikin rotary compressor.
These models are DAIKIN ONE+™ and ComfortNetTM ready.
There are a number of design characteristics which are different
from the traditional compressors.
DZ20VC models use "FVC50K" which is NOT compatible with
mineral oil based lubricants like 3GS. "FVC50K" oil (required by
the manufacturer) must be used if additional oil is required.
NOTE: For models DZ20VC0601B* or earlier, use a Daikin Scroll
compressor "FVC68D" oil"
COOLING
The refrigerant used in the system is R-410A. It is a clear, color-
less, non-toxic and non-irritating liquid. R-410A is a 50:50 blend
of R-32 and R-125. The boiling point at atmospheric pressure is
-62.9°F.
A few of the important principles that make the refrigeration cycle
possible are: heat always flows from a warmer to a cooler body.
Under lower pressure, a refrigerant will absorb heat and vapor-
ize at a low temperature. The vapors may be drawn off and con-
densed at a higher pressure and temperature to be used again.
The indoor evaporator coil functions to cool and dehumidify the
air conditioned spaces through the evaporative process taking
place within the coil tubes.
NOTE: The pressures and temperatures shown in the refrigerant
cycle illustrations on the following pages are for demonstration
purposes only. Actual temperatures and pressures are to be ob-
tained from the "Expanded Performance Chart".
Liquid refrigerant at condensing pressure and temperatures leaves
the outdoor condensing coil through the drier and is metered
into the indoor coil through the metering device. As the cool, low
pressure, saturated refrigerant enters the tubes of the indoor
coil, a portion of the liquid immediately vaporizes. It continues
to soak up heat and vaporizes as it proceeds through the coil,
cooling the indoor coil down to about 48°F.
Heat is continually being transferred to the cool fins and tubes of
the indoor evaporator coil by the warm system air. This warming
process causes the refrigerant to boil. The heat removed from the
air is carried off by the vapor.
As the vapor passes through the last tubes of the coil, it becomes
superheated. That is, it absorbs more heat than is necessary to
vaporize it. This is assurance that only dry gas will reach the
compressor. Liquid reaching the compressor can weaken or break
compressor valves.
The compressor increases the pressure of the gas, thus adding
more heat, and discharges hot, high pressure superheated gas
into the outdoor condenser coil.
In the condenser coil, the hot refrigerant gas, being warmer than
the outdoor air, first loses its superheat by heat transferred from
the gas through the tubes and fins of the coil. The refrigerant now
becomes saturated, part liquid, part vapor and then continues to
give up heat until it condenses to a liquid alone. Once the vapor is
fully liquefied, it continues to give up heat which subcools the
liquid, and it is ready to repeat the cycle.
The inverter system can stop the compressor or outdoor fan to
protect the unit. The inverter system can run higher compressor
speed than required from thermostat to recover compressor oil
that flows.
HEATING
The heating portion of the refrigeration cycle is similar to the
cooling cycle. By de-energizing the reversing valve solenoid coil,
the flow of the refrigerant is reversed. The indoor coil now be-
comes the heat pump condenser coil, and the outdoor coil be-
comes the evaporator coil. The check valve at the outdoor coil
will be forced closed by the refrigerant flow, thereby utilizing the
outdoor expansion device. An electronic expansion valve meters
the condensed refrigerant to the outdoor coil.
DEFROST CYCLE
The defrosting of the outdoor coil is controlled by the Control
Board and the outdoor coil temperature thermistor and defrost
sensor. The outdoor coil temperature thermistor (Tm) sensor is
clamped to a return bend entering the outdoor coil and the de-
frost sensor at bottom flowrator leg at outdoor coil outlet. De-
frost timing periods of 30, 60, 90 or 120 minutes may be selected
via the thermostat setting. Control Board will initiate time de-
frost at the interval selected from the thermostat. During opera-
tion, the microprocessor on the Control Board checks the two
coil and defrost temperature (Tmand Tb) via sensors every 5 sec-
onds in heating mode. When the Control Board detects the coil
temperature to be high enough (approximately 54 °F) and defrost
sensor more than 43 °F for 30 seconds, the defrost cycle is termi-
nated and the timing period is reset. The field service personnel
can also advance a heat pump to the defrost cycle by selecting
“force defrost” option from thermostat.

SYSTEM OPERATION
11
SYSTEM STARTUP TEST
A system test is now required to check the equipment settings
and functionality. Once selected, it checks the equipment for
approximately 5 - 15 minutes. System test may exceed 15
minutes if there is an error. Refer to the Troubleshooting
section, if error code appears. Before starting the SYSTEM TEST,
turn off the electric heater and gas furnace. NOTE: If the unit is
attempting to run SYSTEM TEST in under 20° F ambient tempera-
ture, the unit may not be able to complete the test due to low
suction pressure. In such a case, re-run the SYSTEM TEST when
the ambient temperature exceeds 20° F.
SET THERMOSTAT TO CHARGE MODE
If required additional charging amount cannot be charged to
the system without operation, then use this “CHARGE MODE".
When adjusting "Sub cooling", use this "CHARGE MODE".
CHARGE MODE allows for charging of the system. System
operates for a duration of approximately one hour while the
equipment runs at full capacity. After one hour, the CHARGE
MODE ends and the system resumes normal thermostat opera-
tion.
Before starting the CHARGE MODE, turn off the electric heater.
HEAT PUMP WITH OUTDOOR TEMPERATURE LOCKOUTS
It is recommended to set the outdoor temperature lockouts
during the initial themostat set up. Heat pump (compressor)
lockout temperature will enable the compressor to be turned off
and switch heating source from refrigeration to auxiliary/
secondary heating under low outdoor ambient conditions.
Auxiliary (Backup) heat lockout temperature will enable
auxiliary/secondary heating to be turned on when outdoor
temperature is much higher than indoor temperature,
compressor might stop operating under this circumstance.
Line Set Length Range
(ft.)
Compressor Lockout Temperature
(F°)
0 to 100 15
100 to 200 20
BOOST MODE
BOOST MODE enables the system to operate at a higher com-
pressor speed than rated maximum compressor speed and
satisfy the structural load more effectively during higher
ambient outdoor conditions. BOOST MODE is initiated by an
outdoor temperature sensor located in the outdoor unit. Please
note that outdoor equipment operational sound levels may
increase while the equipment is running in BOOST MODE.
Disabling BOOST MODE will provide the quietest and most
efficient operation.
N INITIAL POWER STAR UP THE OUTDOOR UNIT WILL DISPLAY CODE
SIGNALING THAT INITIAL TEST MUST BE RUN OLLOW
THE HERMOSTAT SETUP SCREEN TO ENTER APPLICATION UNIQUE
INFORMATION EE THERMOSTAT MANUAL FOR DETAILED
INFORMATION
O - ,
E11, SYSTEM . F
T -
. S
.
NOTICE
NOTE: BOOST MODE applies to DZ20VC0**1AB or later model
revisions. BOOST MODE performance is most effective when
paired with an electronic expansion valve enabled indoor unit.
BOOST MODE is ON by default and is activated when the
outdoor temperature reaches 105° F. BOOST MODE can be
disabled and enabled and the activation temperature adjusted.
For detailed procedure to access the these functions, please
visit the Daikin One+ Smart Thermostat website at http://
www.daikinone.com. If using a CTK04 thermostat, please see
the addendum for further instructions.
DEHUMIDIFICATION
The thermostat reads the indoor humidity level and allows the
user to set a dehumidification target based on these settings. The
thermostat controls the humidity level of the conditioned space
using the cooling system. Dehumidification is engaged whenever
a cooling demand is present and structural humidity levels are
above the target level. When this condition exists, the circulating
fan output is reduced, increasing system run time, over cooling
the evaporator coil and ultimately removing more humidity from
the structure than if only in cooling mode. The thermostat also
allows for an additional overcooling limit setting from 0°F to 3°F
setup. This allows the cooling system to further reduce humidity
by lowering the temperature up to 3°F below the cooling setpoint
in an attempt to better achieve desired humidity levels.
DEHUMIDIFICATIONTIPS*
For effective dehumidification operation:
• Ensure "Dehumidification" is not set to "OFF"
-For detailed procedure to access this function, please
visit the DAIKIN ONE+ Smart Thermostat website at
http://www.daikinone.com. If using a CTK04 thermo-
stat, please see the addendum for further instructioins.
• Verify the cooling airflow profile (cool profiles) is set to
"Profile D".
-See the Cool Set-up section of the Installation Manual
for complete airflow profile details.
-By default, "Dehumidification" is standard and the
cooling airflow profile is set to "ProfileD"
• For additional dehumidification control, airflow settings
are field adjustable and can be fine-tuned to a value that
is comfortable for the application from a range of Cool
Airflow Trim.
• In addition, the system can have Enhanced
Dehumidification operation in setting "A", "B", or "C" of
dehumidification based on dehumidification demand.
-See the Dehumidification Select section for more de-
tail. *The specification of DZ20VC0241BD, 0361BC,
0481BC, and 0601BC or earlier models are different
from this specification. For details, see the
Installation Manual or Service Manual that matches
the Major and Minor revision of the model name.

SYSTEM OPERATION
12
Daikin One+ System Advanced Features
The Daikin One+ system permits access to additional system
information, advanced setup features, and advanced
disgnostic/troubleshooting features. These advanced features
are organized into a menu structure. For detailed functions
and menu layout, please visit the Daikin One+ Smart
Thermostat websire at http://www.daikinone.com. (If using a
CTK04 thermostat, please see the addendum for further
instructions.)
ERROR HISTORY
This menu provides access to the most recent faults.
The recent system error histories are displayed on the screen.
Errors are stored in order from most recent to least re-cent.
Any consecutively repeated error is stored only once.
NOTE: It is highly recommended that the error history be
cleared after performing maintenance or servicing the system.
STATUS
This menu displays information about the systems current
status.
This menu can be utilized to confirm correct functionality of
the equipment and for troubleshooting purposes.
PUMP DOWN / CHARGE MODE
This function can be enabled in this menu.
S ET 7-S EGMENT M ODE D ISPLAY T O P UMP D OWN
Please follow the following sequence to enter PUMP DOWN to
accumulate the refrigerant to outdoor unit by 7 Segment Mode.
Do not operate COOL ON mode to enter PUMP DOWN. Before
start-ing the PUMP DOWN operation, change indoor fan trim,
delay and profile back to default and stop electric heater and
gas furnace.
Remove if no trim feature. In this operation, the gas and liquid
service valve should be opened.
1. Set 7-segment display to SCREEN 4 (SETTING MODE 2) Setting
No. 8 and change the display from “-01” to “-00”. System will
then automatically start PUMP DOWN operation.
For information on how to set 7-segment display, see the
section SETTING THE MODE DISPLAY in this manual.
2. Approximately one minute later, the compressor should start
operating. Check the amperage at the compressor wiring to
see the compressor operation status. Unit display error code
E11 (System verification Test) once the PUMP DOWN
operations starts.
3. Close liquid service valve approximately two minutes after
compressor has come on.
4. Compressor will come to a stop automatically. Close the gas
service valve immediately after the compressor
stops.Aftercompletion of PUMP DOWN, unit shows error code
“E11”.
NOTE: Refrigerant cannot be collected to the outdoor unit
completely if the system is overcharged or if there is a delay in
closing the liquid service valve and gas service valve. Evacuate
the left over refrigerant from the system using a recovery
machine.
S YSTEM T EST
The mandatory system verification test is enabled from this
SYSTEM TEST menu, which enables a functional check of the
equipment, in addition to ensuring proper stop valve position.
C OOL S ETTINGS
This menu allows for the adjustment of several cooling
performance variables. Cool Airflow Trim (*1), Cool Airflow
Profiles, Cool Airflow ON Delay, Cool Airflow OFF Delay and
Dehumidification Select (some enable option or off ) can be
adjusted in this menu.
*1
1) At Cool and Heat Hi speed trim, DZ20VC0601* with
D*96VC0804C, D*97MC0804C and DM80VC0804C combination
trim more than 5% settings are invalid. Trimmed up CFM makes
miss matching error.
2) At Cool Hi speed trim, Other than the above, depending on
the connected indoor unit, there are restrictions on the positive
side Trim setting.
If you want to change the Cool Airflow Trim to positive side, be
sure to confirm the Airflow Trim restrictions in the latest
indoor unit installation manual. The latest manual can be
obtained from the website “DAIKIN CITY (Installation Manual/
Unitary Split System)” or “PartnerLink(InfoFinderPlus/
Literature)”.
[DAIKIN CITY URL] https://www.daikincity.com/Library/
[PartnerLink URL]
https://partnerlinkmarketing.goodmanmfg.com/goodman/info-
finder-plus
3) At Cool Intermediate and Low speed trim, The Inverter system
uses lower compressor speed and lower indoor unit CFM to
optimize system performance.
To obtain 100% CFM for home circulation, use full Trim setting
instead of Int/ Low speed.
This is recommended for applications with unusually cold
return temperatures such as basements.
COOL AIRFLOW PROFILE (Cool Profile)
• Profile A provides only an OFF delay of one (1) minute at
100% of the cooling demand airflow.
• 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.

SYSTEM OPERATION
13
• Profile C ramps up to 82% of the full cooling demand airflow
and operates there for approximately 7 1/2 minutes. The
motor then steps up to the full demand airflow. Profile C
also has a one (1) minute 100% OFF delay.
• Profile D (default) ramps up to 50% of the demand for
1/2 minute, then ramps to 82% of the full cooling demand
airflow and operates there for approximately 7 1/2 minutes.
The motor then steps up to the full demand airflow. Profile D
has a 1/2 minute at 50% airflow OFF delay.
DEHUMIDIFICATION SELECT*
When Dehumidification mode exists, the circulating fan output
is reduced, increasing system run time, over cooling the
evaporator coil and ultimately removing more humidity from
the structure than if only in cooling mode.
The system can have Dehumidification operation in setting
“Standard”, “A”, “B” or “C” of “dehumidificatoin” menu
based on dehumidification demand.
Setting “Standard” allows for the widest compressor operation
range with lower CFM than Cooling mode.
In the Enhanced Dehumidification (setting A, B and C) the
indoor airflow is lower than Standard Dehumidification
(Standard).
Setting “A” allows for the same compressor operation range as
standard Dehumidification with lower CFM than standard
dehumidification (Standard).
Setting “B” limits compressor operation range and keeps high
dehumidification capacity.
In setting “C” the system runs fixed at 100% compressor and
airflow. See Figure 1.
NOTE: In high humidity environments, sweating on supply
ducts, cased coils or air handler cabinets can become an issue
in Enhanced Dehumidification operation. It is strongly
recommended covering then with 2" fiberglass insulation for
these installations.
* The specification of DZ20VC0241BD, 0361BC, 0481BC and
0601BC or earlier models are different from this specification.
For details, see the Installation Manual or Service Manual that
matches the Major and Minor revision of model name.
MAX COMPRESSOR RPS / MAX RPS OFFSET
Max compressor speed at which the outdoor unit will operate
can be changed using thermostat. Max compressor speed can
be changed to get the required capacity or efficiency.
Once the maximum speed is set, the system operates between
the set maximum speed and default low speed.
Based on the compressor speed displayed in “MAX COMPRES-
SOR RPS” the maximum compressor speed can be Increased or
decreased in the “MAX RPS OFFSET” menu.
HEAT SETTING
This menu allows for the adjustment of several heating
performance variables. Heat Airflwo trim (*1), Heat Airflow ON
Delay, Heat Aifflow OFF Delay and timed Defrost interval can be
adjusted in this menu. Time interval of 30, 60, 90, and 120
minutes between two defrost cycles can be set to suit the
weather conditions and performance of the unit.
SET THERMOSTAT TO ADJUST INDOOR AIR CFM TRIM *1
User can change the airflow trim at high, intermediate and low
for cooling and heat pump mode.
Select:
Cool/Heat Airflow Trim (High): high speed cooling/heating
Cool/Heat Airflow Trim (int): intermediate speed cooling/
heating
Cool/Heat Airflow Trim(Low): low speed cooling/heating Under
each trim setting, the airflow can be increased or decreased by
a certain percentage.
*1
1) At Cool and Heat Hi speed trim, DZ20VC0601* with
D*96VC0804C, D*97MC0804C and DM80VC0804C combination
trim more than 5% settings are invalid. Trimmed up CFM makes
miss matching error.
2) At Cool Hi speed trim, Other than the above, depending on
the connected indoor unit, there are restrictions on the positive
side Trim setting.
If you want to change the Cool Airflow Trim to positive side, be
sure to confirm the Airflow Trim restrictions in the latest
indoor unit installation manual. The latest manual can be
obtained from the website “DAIKIN CITY
(Installation Manual/Unitary Split System)” or
“PartnerLink(InfoFinderPlus/ \Literature)”.

SYSTEM OPERATION
14
[DAIKIN CITY URL]
https://www.daikincity.com/Library/
[PartnerLink URL]
https://partnerlinkmarketing.goodmanmfg.com/goodman/info-
finder-plus
3) At Cool Intermediate and Low speed trim, The Inverter system
uses lower compressor speed and lower indoor unit CFM to
optimize system performance.
To obtain 100% CFM for home circulation, use full Trim setting
instead of Int/ Low speed.
This is recommended for applications with unusually cold
return temperatures such as basements.
SET THERMOSTAT TO ADJUST INDOOR COOL ON DELAY AND COOL
OFF DELAY
Select “Cool ON Delay” or “Cool OFF Delay”.
Check the installation manual of the indoor unit for more
details.

SYSTEM OPERATION
15
LEGEND:
Tl = Thermistor (Outdoor Liquid Temperature)
Td = Thermistor (Discharge Temperature)
Ta = Thermistor
(
Outdoor Air Tem
p
erature
)
HP/LP sensor = High/Low Pressure Sensor
HPS = High Pressure Switch
Tm = Thermistor (Outdoor Coil Temperature)
Piping Diagram with TXV applicable indoor unit
Hex
Fan
Motor
Filter
dryer
Stop
Va lv e
(Liquid)
Ball Valve
(Gas)
Fan
Motor
Hex
HP/LP
HP/LP sensor
Tm
Thermistor
Ref cooling
Ta Ther mistor
Outdoor unit
Indoor unit
TXV
Check
valve
Td Thermistor
Filter
Compressor
Capillary tube
HPS
Oil
separator
Accumulator
TThermistor
Reversing
Va l v e
Check
valve
EEV
Filter
Filter
HE PECIFICATION OF OR EARLIER MODELS ARE DIFFERENT FROM THIS SPECIFICATION OR DETAILS SEE THE SERVICE
MANUAL THAT MATCHES THE MAJOR REVISION OF MODEL NAME
T S DZ20VC0601B* . F ,
.
NOTICE
COOLING CYCLE

SYSTEM OPERATION
16
LEGEND:
Tl = Thermistor (Outdoor Liquid Temperature)
Td = Thermistor (Discharge Temperature)
Ta = Thermistor (Outdoor Air Temperature)
Tm = Thermistor (Outdoor Coil Temperature)
Tli = Thermistor (Indoor Liquid Temperature)
Tgi = Thermistor (Indoor Gas Temperature)
ID HP/LP sensor = Indoor High/Low Pressure Sensor
OD HP/LP sensor = Outdoor High/Low Pressure Sensor
HPS = Hi
g
hPressureSwitch
HE PECIFICATION OF OR EARLIER MODELS ARE DIFFERENT FROM THIS SPECIFICATION OR DETAILS SEE THE SERVICE
MANUAL THAT MATCHES THE MAJOR REVISION OF MODEL NAME
T S DZ20VC0601B* . F ,
.
NOTICE
COOLING CYCLE

17
TROUBLESHOOTING
A VOID CONTACT WITH THE CHARGED AREA .
•N
EVER TOUCH THE CHARGED AREA BEFORE CONFIRMING THAT THE RESIDUAL VOLTAGE IS 50 VOLTS OR LESS .
1. S
HUT DOWN THE POWER AND LEAVE THE CONTROL BOX FOR 10 MINUTES .
2. M
AKE SURE TO TOUCH THE E ARTH GROUND TERMINAL TO RELEASE THE STATIC ELECTRICITY FROM YOUR BODY ( TO PREVENT FAILURE OF THE PC BOARD ).
3. M
EASURE THE RESIDUAL VOLTAGE IN THE SPECIFIED MEASUREMENT POSITION USING A VOM WHILE PAYING ATTENTION NOT TO TOUCH THE CHARGED AREA .
4. I
MMEDIATELY AFTER MEASURING THE RESIDUAL VOLTAGE , DISCONNECT THE CONNECTORS OF THE OUTDOOR UNIT ’ S FAN MOTOR . (I F THE FAN BLADE ROTATES BY
STRONG WIND BLOWING AGAINST IT , THE CAPACITOR WILL BE CHARGED, CAUSING THE DANGER OF ELECTRICAL SHOCK .)
WARNING
Outdoor Normal Temperature Operating Range: 67-115°F / Indoor Normal Temperature Operating Range: 65 - 85°F
POSSIBLE CAUSE
X IN ANALYSIS GUIDE INDICATE
"POSSIBLE CAUSE"
Comp discharge temp > 200F Comp discharge temp < 105F Comp discharge SH > 70F Comp discharge SH < 20F High pressure > 490psi High pressure < 255psi LSV SC > 12F LSV SC < 4F OD SSV SH > 20F OD SSV SH < 4F Low pressure > 185psi Low pressure < 100psi Requested % demand < Actual Requested % demand > Actual Repeated stop/start Weak cooling No switch cooling Noise Stop operation
Liquid stop valve does not fully open XXXXX XXXXX
Gas stop valve does not fully open XX XXXX
Line set restriction XXXXX XXXXX
Line set length is too long XXXXX
Blocked filter-dryer XXXXX XXXXX
OD EEV coil failure XXX X
OD EEV failure XXX
ID EEV coil failure XXXXXXXXXXXXXXXX X
ID EEV failure XXXXXXXXXXXXXXXX
Check valve failure – Blocked XXX XX XXXX
High Pressure switch failure X
Pressure sensor failure XXXXXXX
Discharge temp sensor failure XXXX XXXX X
Coil temp sensor failure XXX XXXX X
Defrost sensor failure
Liquid temp sensor failure
Ambient temp sensor failure XXX XXXX
OD recirculation XXX XXXX
ID recirculation XX XXXXXX
Dirty OD Heat-exchanger XXX XXXX
Dirty ID Heat-exchanger X X X X XXXXX
Outdoor Ambient temp is too high XXX X XXXX
Outdoor Ambient temp is too low X X XX XXXXX
ID suction temp is too high XX
ID suction temp is too low X X X X XXXXX
Mixture of non-condensible gas XXX XX XXXXX
OD fan motor failure X X X X XXX XX
RV failure X X X X XXXX X
RV coil failure X X X X XXXX X
Over charge XXXXXXXXXX
Under charge XXX X XX X X X
Leak XXX X XX X XXX X
TXV failure XXXXXXXXXXXXXXXX
TXV is s mall XXXXX X X
TXV is big XXXXXXX X
OD Control Board Failure X
ID Failure XXXXXXXXXXXXXXXXX X
Compressor failure XXX X X XXX XX
Cooling loop is not attached XXX
Cooling loop grease is not enough XXX
Compressor and Gas furnace are operating at the same time X
Low ID CFM XX XXXXXX X
COOLING ANALYSIS CHART

18
A VOID CONTACT WITH THE CHARGED AREA .
•N
EVER TOUCH THE CHARGED AREA BEFORE CONFIRMING THAT THE RESIDUAL VOLTAGE IS 50 VOLTS OR LESS .
1. S
HUT DOWN THE POWER AND LEAVE THE CONTROL BOX FOR 10 MINUTES .
2. M
AKE SURE TO TOUCH THE E ARTH GROUND TERMINAL TO RELEASE THE STATIC ELECTRICITY FROM YOUR BODY ( TO PREVENT FAILURE OF THE PC BOARD ).
3. M
EASURE THE RESIDUAL VOLTAGE IN THE SPECIFIED MEASUREMENT POSITION USING A VOM WHILE PAYING ATTENTION NOT TO TOUCH THE CHARGED AREA .
4. I
MMEDIATELY AFTER MEASURING THE RESIDUAL VOLTAGE , DISCONNECT THE CONNECTORS OF THE OUTDOOR UNIT ’ S FAN MOTOR . (I F THE FAN BLADE ROTATES BY
STRONG WIND BLOWING AGAINST IT , THE CAPACITOR WILL BE CHARGED, CAUSING THE DANGER OF ELECTRICAL SHOCK .)
WARNING
TROUBLESHOOTING
POSSIBLE CAUSE
X IN ANALYSIS GUIDE INDICATE
"POSSIBLE CAUSE"
Comp discharge temp > 200F Comp discharge temp < 105F Comp discharge SH > 70F Comp discharge SH < 20F High pressure > 490psi High pressure SSV< 270psi High pressure LSV< 270psi LSV SC > 12F LSV SC < 4F Low pressure < 40psi Requested % demand < Actual % Requested % demand > Actual % Repeated stop/start Weak heating No switch heating Noise Incomplete defrost operation Stop operation Sweating liquid line
Liquid stop valve does not fully open XXX XXXXX XX
Gas stop valve does not fully open X X X XX XXX X
Line set restriction X X X XX XXX X X
Line set length is too long XX X
Blocked filter-dryer X X X XX XXX X X
OD EEV coil failure XXXXXXXXXXXXXX XX
OD EEV failure XXXXXXXXXXXXXX XX
ID EEV coil failure XXXXXXXXXX XXX
ID EEV failure XXXXXXXXXX XXX
Check valve failure – Leakage XX XXXX X
High Pressure switch failure X
Pressure sensor failure XXXXXXX XXXX X
Discharge temp sensor failure XXXX XXXX X
Coil temp sensor failure X XXX XX
Defrost sensor failure X XXX XX
Liquid temp sensor failure XX XX
Ambient temp sensor failure X X XXX XX
OD recirculation X X XX X XXX
ID recirculation XXX XXX
Dirty OD Heat-exchanger X X XX X XXX
Dirty ID Heat-exchanger XXX XXX
Outdoor Ambient temp is too high X XXX XX
Outdoor Ambient temp is too low XXX XX XX XXX
ID suction temp is too high X X XXX
ID suction temp is too low XX X
Mixture of non-condensible gas X X X XX XXX
OD fan motor failure X X X XXX X
RV failure X XX XXXX XX
RV coil failure X XX XXXX XX
Over charge XXX X XXXX XX
Under charge XXX XX XX XX X
Leak XXX XX XX XX X
TXV failure X X X XX XXX
TXV size is small X
TXV size is big
ID failure XXXXXXXXXXXXXX XXXX
OD Control Board failure X
Compressor failure XXXX XX XXX XXX
Cooling loop is not attached XXX
Cooling loop grease is not enough XXX
Compressor and Gas furnace are operating at the same time XX
Low ID CFM XXXXXXX
HEATING ANALYSIS CHART
Outdoor Normal Temperature Operating Range: 17-62°F / Indoor Normal Temperature Operating Range: 65 - 85°F

19
HIGH VOLTAGE!
Disconnect ALL power before servicing or installing. Multiple power sources may be present. Failure to
do so may cause property damage, personal injury or death.
TABLE OF CONTENTS
S-1 CHECKING VOLTAGE ..................................................... 20
S-2 CHECKING WIRING ...................................................... 20
S-3 CHECKING THERMOSTAT AND WIRING ........................ 20
S-3A THERMOSTAT AND WIRING .......................................... 20
S-3E DAIKIN COMMUNICATING THERMOSTAT ..................... 21
S-4 CHECKING TRANSFORMER AND CONTROL CIRCUIT........21
S-12 CHECKING HIGH PRESSURE SWITCH ............................ 22
S-13 CHECKING INDOOR AND
OUTDOOR HI/LOW PRESSURE SENSOR ....................... 22
S-17 CHECKING COMPRESSOR ............................................ 22
S-17A RESISTANCE TEST .......................................................... 23
S-17B GROUND TEST .............................................................. 23
S-26 TESTING TEMPERATURE SENSORS
AND EEV COIL RESISTANCE ........................................ 23
S-40A MBVC**00AA-1 HEATER CONTROL .............................. 24
S-40B DV**PEC HEATER CONTROL ......................................... 25
S-50 CHECKING HEATER LIMIT CONTROL(S) ......................... 26
S-52 CHECKING HEATER ELEMENTS ...................................... 26
S-60 ELECTRIC HEATER (OPTIONAL ITEM) ............................ 26
S-61A CHECKING HEATER LIMIT CONTROL(S) ......................... 27
S-61B CHECKING HEATER FUSE LINK
(OPTIONAL ELECTRIC HEATERS) ................................... 27
S-100 REFRIGERATION REPAIR PRACTICE ............................... 28
S-101 LEAK TESTING (NITROGEN OR NITROGEN-TRACED) ..... 28
S-102 EVACUATION ................................................................ 28
S-103 CHARGING .................................................................... 29
SERVICING TABLE OF CONTENTS
S-104 CHECKING COMPRESSOR EFFICIENCY ......................... 30
S-105B THERMOSTATIC EXPANSION VALVE ............................... 30
S-106 OVERFEEDING .............................................................. 30
S-107 UNDERFEEDING ........................................................... 30
S-108 SUPERHEAT .................................................................. 30
S-109 CHECKING SUBCOOLING .............................................. 31
S-110 CHECKING THERMOSTATIC
EXPANSION VALVE OPERATION .................................... 32
S-114 NON-CONDENSABLES ................................................... 32
S-115 COMPRESSOR BURNOUT ............................................. 33
S-120 REFRIGERANT PIPING .................................................. 33
S-202 DUCT STATIC PRESSURES
AND/OR STATIC PRESSURE DROP ACROSS COILS ......... 37
S-203 AIR HANDLER EXTERNAL STATIC ................................... 37
S-204 COIL STATIC PRESSURE DROP ....................................... 38
HE PECIFICATION OF OR EARLIER MODELS ARE DIFFERENT FROM THIS SPECIFICATION OR DETAILS SEE THE SERVICE
MANUAL THAT MATCHES THE MAJOR REVISION OF MODEL NAME
T S DZ20VC0601B* . F ,
.
NOTICE

SERVICING
20
S-1 CHECKING VOLTAGE
1. Remove outer case, control panel cover, etc., from unit being
tested.
With power ON:
L INE V OLTAGE NOW PRESENT .
WARNING
2. Using a voltmeter, measure the voltage across terminals L1
and L2 of the contactor for the heat pump condenser unit or
at the field connections for the air handler or heaters.
ComfortNetTM Ready Heat Pump Condenser Units: Measure
the voltage across the L1 and L2 lugs on the unitary (UC)
control.
3. No reading - indicates open wiring, open fuse(s) no power or
etc., from unit to fused disconnect service. Repair as needed.
4. With ample voltage at line voltage connectors, energize the
unit.
voltage min. max.
Outdoor Unit, Air Handler,
Modular Blower, Heater Kit 208/230 197 253
Gas Furnaces 115 103 126
Unit Suply Voltage (VAC)
Unit Type
NOTE: When operating electric heaters on voltages other than
240 volt, refer to the System Operation section on electric heat-
ers to calculate temperature rise and air flow. Low voltage may
cause insufficient heating.
S-2 CHECKING WIRING
HIGH VOLTAGE !
D ISCONNECT ALL POWER BEFORE SERVICING OR
INSTALLING . M ULTIPLE POWER SOURCES MAY BE
PRESENT . F AILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE , PERSONAL INJURY OR DEATH .
WARNING
1. Check wiring visually for signs of overheating, damaged in-
sulation and loose connections.
2. Use an ohmmeter to check continuity of any suspected open
wires.
3. If any wires must be replaced, replace with comparable gauge
and insulation thickness.
S-3 CHECKING THERMOSTAT AND WIRING
Communicating Thermostat Wiring: The maximum wire length
for 18 AWG thermostat wire is 250 feet.
S-3A THERMOSTAT AND WIRING
L INE V OLTAGE NOW PRESENT .
WARNING
With power ON, thermostat calling for cooling/heating.
1. Use a voltmeter to check for 24 volt at thermostat wires C and
R in the indoor unit control panel.
2. No voltage indicates trouble in the thermostat, wiring or trans-
former source.
3. Check the continuity of the thermostat and wiring. Repair or
replace as necessary.
L INE V OLTAGE NOW PRESENT .
WARNING
Resistance Heaters
With power ON:
1. Set room thermostat to a higher setting than room tempera-
ture so both stages call for heat.
2. With voltmeter, check for 24 volt at each heater relay.
3. No voltage indicates the trouble is in the thermostat or wir-
ing.
4. Check the continuity of the thermostat and wiring. Repair or
replace as necessary.
NOTE: Consideration must be given to how the heaters are wired
(O.D.T. and etc.). Also safety devices must be checked for continu-
ity.