Carrier 40MUAAQ18XB3 User manual

Specifications subject to change without notice.
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS ....................................................... 1
INTRODUCTION............................................................................ 1
MODEL NUMBER NOMENCLATURE ....................................... 2
AUXILLIARY CONTACTS FOUND ON THE MAIN BOARD .. 3
ROTARY AND DIP SWITCHES ................................................... 6
INDOOR UNIT WIRING................................................................ 8
WIRING REQUIREMENTS ........................................................... 9
CONNECTION DIAGRAMS ......................................................... 10
WIRING DIAGRAMS..................................................................... 11
REFRIGERANT LINES .................................................................. 12
TROUBLESHOOTING ................................................................... 13
DIAGNOSIS AND SOLUTION...................................................... 16
DISASSEMBLY INSTRUCTIONS ................................................ 35
APPENDICES.................................................................................. 41
SAFETY CONSIDERATIONS
Installing, starting up, and servicing air-conditioning equipment can
be hazardous due to unit pressures, electrical components, and
equipment location (roofs, elevated structures, etc.).
Only trained, qualified installers and service mechanics should install,
start-up, and service this equipment.
Untrained personnel can perform basic maintenance functions such as
coil cleaning. All other operations should be performed by trained
service personnel only.
When working on the equipment, observe the precautions in the
literature and on tags, stickers, and labels attached to the equipment.
Follow all safety codes. Wear safety glasses and work gloves. Keep a
quenching cloth and fire extinguisher nearby when brazing. Use care
in handling, rigging, and setting bulky equipment.
Read this manual thoroughly and follow all the warnings or cautions
included in the literature and attached to the unit. Consult local building
codes and the National Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety-alert symbol .
When you see this symbol on the unit and in instructions or manuals,
be alert to the potential for personal injury. Understand these signal
words: DANGER, WARNING, and CAUTION.
These words are used with the safety-alert symbol. DANGER
identifies the most serious of hazards which will result in severe
personal injury or death. WARNING signifies hazards which could
result in personal injury or death. CAUTION is used to identify
unsafe practices which may result in minor personal injury or product
and property damage. NOTE is used to highlight suggestions which
will result in enhanced installation, reliability, or operation.
INTRODUCTION
This service manual provides the necessary information to service,
repair, and maintain the indoor units. This manual contains an
“DISASSEMBLY INSTRUCTIONS” on page 35 with data required to
troubleshoot issues. Use the “TABLE OF CONTENTS” on page 1 to
locate a desired topic.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death. Before installing, modifying, or servicing the unit, the
main electrical disconnect switch must be in the OFF position.
There may be more than 1 disconnect switch. Lock out and tag
switch with a suitable warning label.
WA R N I N G
EXPLOSION HAZARD
Failure to follow this warning could
result in death, serious personal
injury, and/or property damage.
Never use air or gases containing
oxygen for leak testing or operating
refrigerant compressors. Pressurized
mixtures of air or gases containing
oxygen can lead to an explosion.
WAR NI NG
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Do not bury more than 36 in. (914 mm) of refrigerant pipe in the
ground. If any section of pipe is buried, there must be a 6 in. (152
mm) vertical rise to the valve connections on the outdoor units. If
more than the recommended length is buried, refrigerant may
migrate to the cooler buried section during the extended periods
of unit shutdown. This causes refrigerant slugging and could
possibly damage the compressor at start-up.
CAUTION
Service Manual
40MUAA
Air Handler Unit
Sizes 18 to 60

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
2
MODEL NUMBER NOMENCLATURE
Table 1 — Unit Sizes
KBTUH V-PH-HZ ID MODEL NO.
18
208/230-1-60
40MUAAQ18XB3
24 40MUAAQ24XB3
30 40MUAAQ30XB3
36 40MUAAQ36XA3
36 40MUAAQ36XB3
48 40MUAAQ48XA3
60 40MUAAQ60XA3
INDOOR UNIT
40
MU AQ24 XA3
40 = INDOOR UNIT
M = SUPPLIER
U = UNITARY VOLTAGE
3 = 208/230-1-60
INDOOR FAN COIL UNIT TYPE
A = AIR HANDLER
UNIT TYPE
Q = Heat Pump X = Indoor Unit
NOMINAL CAPACITY
18 - 1 1/2 TON
24 - 2 TONS
30 - 2 1/2 TONS
36 - 3 TONS
48 - 4 TONS
60 - 5 TONS
A = Light Commercial
B = Non Light Commercial
A
MAJOR SERIES
Lorem ipsum
21
22 10001
Week of Manufacture Sequential Serial Number
V
V = ALL MODELS
Year of Manufacture
Use of the AHRI Certified
TM Mark indicates a
manufacturer’s
participation in the
program For verification
of certification for individual
products, go to
www.ahridirectory.org.

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
3
AUXILLIARY CONTACTS FOUND ON THE MAIN BOARD
Work Terminal Port CN23 - Normally Open Dry Contact (Output)
•The WORK terminal port is linked to the unit's indoor blower
• When the indoor blower is off, the contact is open
• When the indoor blower is running, the contact is closed
• There is no voltage from CN23, power is provided from the external control system and not from the unit.
• The contacts are rated at 250VAC and 10 AMP maximum
• If an active 24V signal output is required, G and C ports (thermostat connections) may be used instead.
Fig. 1 — Auxiliary Contacts
ALARM Terminal Port CN33 - Normally Open DRY CONTACT (OUTPUT):
• Allows the terminal port to connect to an external ALARM interface or annunciator
• There is no voltage from
CN33 , power is provided from the ALARM system and not from the unit
• The contacts are rated at
250VAC and 10 AMP maximum
• When the unit experiences a problem, the contact closes, and the
ALARM is triggered.
Fig. 2 — Auxiliary Contacts

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
4
WATER LEVEL Switch Terminal Port CN5 - SWITCH INPUT:
• To enable this switch, jumper J1 must be removed
• A field supplied float switch can be directly connected to
CN5
• CLOSED contacts = normal
• OPEN contacts = overflow
• When an overflow condition occurs, a signal is sent to the system to turn it off
•Alarm
EE appears.
Fig. 3 — Auxiliary Contacts
UV LED Terminal Port CN43 - OUTPUT 24VAC:
•The UV LED port is linked to the unit's fan
• When the fan is running, the relay is closed and there is an output of
24VAC through the contacts that can be used to power a compatible UV LED LIGHT
• May also be used to power a pilot relay with 24VAC coil to control other peripherals
NOTE: After the serial number (0223V26809), the CN43 feature is available.
Fig. 4 — Auxiliary Contacts

40MUAA: Service Manual
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5
Auxiliary Contacts found on the 24V interface Board:
Remote control (ON-OFF) terminal port CN2 and jumper JR1 - INPUT:
• Remove the jumper JR1 to enable the ON-OFF function
• When the remote switch is off (
OPEN ); the unit is OFF
• When remote switch is on ( CLOSE ); the unit is ON
• When the remote switch is close/open, the unit responds to the demand within 2 seconds
• When the remote switch is on, you can use the included remote controller or wired controller to operate the unit as normal.
• When the remote switch off, the unit will not respond to the command from the remote controller or wired controller and a CP code is displayed on the
board.
Fig. 5 — Auxiliary Contacts

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
6
ROTARY AND DIP SWITCHES
Micro-Switch Setting:
Fig. 6 —Net Address
Micro-switch S1 and dial-switch S2 are for address setting when the user wants to control the unit with a central controller.
Range: 00-63
Fig. 7 — Unit Configuration
Fig. 8 — Unit Configuration Factory Settings
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
S1+S2
0~F 0~F 0~F 0~F
NETADDRESS
CODE
0~15 16~31 32~47 48~63
FACTORYS ETTING
FOR SETTING NETADDRESS
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0~F ON~OFF
CODE
FACTORY
1 2 3
ON
4
SW1
12 3
ON
4
SW2
1 2 3
ON
4
SW3
S3
12 3
ON
4
SW4
12
ON
S4
24V THERMOSTATS SETTING
SETTI
ON~OFF ON~OFF ON~OFF ON~OFF

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
7
Connectors
Table 2 — Unit Configuration Settings
*NOTE: Auto detection is available after serial number 0223V26809. With this feature active, the system detects the wiring
method according to the 3 control scenarios automatically with all SW1 dip switches set to default.
NOTE: After the serial number (0223V26809) the auto detection feature is available; prior to the serial number cutoff, the
control scenario needs to be set for Scenario 1(SW 1-1 ON) and Scenario 3(SW 1-1 and SW 1-4 ON).
Dial Code Control Scenario Function ON OFF
SW1-1*
OFF for 2 ON for 1 and 3
Please note: SW 1-4
needs to be ON as well
for Scenario 3
Control Function 24 V Communication [Default] Auto Detect or RS485 S1-S2
Communication
SW1-2 1,2 Anti-cold blow protection option NO [Default] YES
SW1-3 1,2,3 Single cooling / heating and cooling
options Cooling [Default] Cooling & Heating
SW1-4*
OFF for 1 and 2 ON for 3
Please note: only active
for scenario 3 when
used with SW 1-1 ON
Control Function Scenario 3 [Default] Auto Detect or Scenario 1
SW2-1 1
Compressor Running Compensation
(Demand working with heat pump+
Electric heat)
Compressor slower speed [Default] Faster Compressor
SW2-1 2
Temperature differential to activate
first stage auxiliary heat (the GAP of
T1 and Ts) Wire controller demand
with heat pump + Electric heat
working together
2F [Default] 4F
SW2-2 2 Electric heat on delay YES [Default] NO
SW2-3 2 Electric auxiliary heating delay to start
time 30 minutes [Default] 15 minutes
SW2-4 2 Compressor/Auxiliary heat outdoor
ambient lockout
The compressor does not operate if
the outdoor temperature is lower than
the temperature represented by S3
[Default] The heater does not operate if
the outdoor temperature is greater than
the temperature represented by S3
Rotary
Switch S3 2Set outdoor temperature Limitation (for auxiliary heating or compressor)
0 means that the temperature
protection is not turned on, the dial
range is 1 through F, 1 equals -4°F
and it increased up to 46°F
SW3-1 1
Maximum continuous runtime allowed
before system automatically stages
up capacity to satisfy set point. This
adds 1 to 5°F to the user set point in
the calculated control point to
increase capacity and satisfy user set
point
30 minutes [Default] 90 minutes
SW3-2 1 Cooling and heating Y/Y2 compressor
speed adjustment. Compressor slower speed [Default] Faster Compressor
SW3-3 1
Compressor Running (demand
working with heat pump+ Electric
heat)
Compressor slower speed [Default] Faster Compressor
SW3-3 2
Temperature differential to activate
second stage auxiliary heating (the
GAP of T1 and Ts) Wire controller
demand with heat pump + Electric
heat working together
4F [Default] 6F
SW3-4 1,3 Fan speed of the COOLING mode
when 24V thermostat is applied for. Turbo Off
SW4 1,2,3 Electric heat nominal CFM adjustment
Available settings are 000/001/010/
011. Each digit corresponds an
individual switch position
(e.g. [SW4-1 OFF, SW4-2 ON,
SW4 -3 OFF] = 010).
S4-1 1,3 Default ON
[Default] For single stage
supplemental heat, W1 and W2 are
connected
For dual stage supplemental heat, W1
and W2 are controlled independently.
S4-2 1,3 DH function selection [Default] Dehumidification
control not available
Dehumidification feature is enabled
through thermostat

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
8
INDOOR UNIT WIRING
Before proceeding with electrical connections, make certain that the
supply voltage, frequency, phase, and ampacity are as specified on the
unit rating plate. Review the unit wiring label for proper field high and
low voltage wiring.
Ensure all electrical connections are in accordance with the NEC and any
local codes or ordinances that may apply. Use copper wire only.
Use the following steps to wire the indoor unit.
NOTE: Wiring in this section is for the base unit ONLY.
1. Prepare the cable for connection.
a. Using wire strippers, strip the insulation from both ends of the
signal cable to reveal about 1/2 in (12mm) of wire.
b. Strip the insulation from both ends of the wires.
c. Use a wire crimper to crimp the fork terminals to the ends of
the wires.
2. Open the indoor unit’s front panel. Use a screwdriver to remove the
cover of the electric control box on the indoor unit.
3. Thread the power cable and the signal cable through the wire outlet.
4. Connect the fork terminals to the terminals. Match the wire colors/
labels with the labels on the terminal block.
5. Firmly screw the fork terminals of each wire to its corresponding
terminal. Refer to the serial number and wiring diagram located on
the cover of the electric control box.
A220802
Fig. 9 — Indoor Unit Power Wiring
NOTE: The electric auxiliary heat wiring diagram is supplied with
the accessories. Paste the wiring diagram in the designated
position after installing the heat modules.
IMPORTANT: A separate power supply is required for an
Auxiliary Electric Heater. Do not power the electric heater
directly from the outdoor unit. Always follow the
recommendations listed in the installation instructions
manuals. Refer to the EHKMB Installation Manual
6. Clamp down the cable with the cable clamp. The cable must not be
loose or put strain on the fork terminals.
7. Reattach the electric box cover.
A220826
Fig. 10 —Controls and Power Terminals on Indoor Unit
(All Sizes)
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in product or property
damage. If a disconnect switch is to be mounted on the unit, select
a location where the drill or fastener will not contact electrical or
refrigerant components.
CAUTION
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death. Field wires on the line side of the disconnect found in the
fan coil unit remain live, even when the pull-out is removed.
Service and maintenance to incoming wiring cannot be performed
until the main disconnect switch (remote to the unit) is turned off.
WAR NI NG
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage or
improper operation. Size the wires in accordance with NEC and
local codes.
CAUTION
While connecting the wires, strictly follow the wiring diagram.
The refrigerant circuit can become very hot.
Keep the interconnection cable away from the copper tube.
CAUTION

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
9
WIRING REQUIREMENTS
Size all wires per the NEC (National Electrical Code) or CEC (Canadian
Electrical Code) and local codes. Use the electrical data from the outdoor
unit (MCA - minimum circuit amps and MOCP - maximum over current
protection), to correctly size the wires and the disconnect fuse or breakers
respectively.
Communication Wiring: There are two options available to establish
communication between the outdoor unit and approved indoor unit.
Table 3 — Options for Establishing Communication
NOTE: Separate power is required for an Auxiliary Electric
Heater.
OPTIONS COMMUNICATION TYPE RECOMMENDED CABLE SIZE
1Non-Polarity RS485
Communication (S1 - S2) 16 AWG (stranded shielded)
2 24V communication 18 AWG 8 conductor
thermostat wire
Refer to the wiring template for the wiring method.
DO NOT connect the power cord to the communication line as
this may damage the system.
WA R N I N G
EQUIPMENT DAMAGE HAZARD
Be sure to comply with local codes while running wire from the indoor
unit to the outdoor unit.
Every wire must be connected firmly. Loose wiring may cause the
terminal to overheat or result in a unit malfunction. A fire hazard may also
exist. Ensure all wiring is tightly connected.
No wire should touch the refrigerant tubing, compressor or any moving
parts.
Disconnecting means must be provided and located within sight and
readily accessible from the system. Route the connecting cable with
conduit through the hole in the conduit panel.
CAUTION
EQUIPMENT DAMAGE HAZARD
Comply with local codes while running wire from the indoor unit to the outdoor
unit. Every wire must be connected firmly. Loose wiring may cause the
terminal to overheat or result in a unit malfunction. A fire hazard may also exist.
Ensure all wiring is tightly connected.
No wire should touch the refrigerant tubing, compressor or any moving parts.
Disconnecting means must be provided and located within sight and readily
accessible from the system. Route the connecting cable with conduit through
the hole in the conduit panel.
CAUTION

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
10
CONNECTION DIAGRAMS
Scenario 1 - Non-Polarity RS485 Communication + 24V Thermostat
This is the preferred method when using a 24V thermostat and when the indoor unit communicates with the outdoor unit via RS485 (S1/S2) protocol.
NOTE: After the serial number (0223V26809), the Auto Discovery feature is available.
Fig. 11 — Scenario 1
Scenario 2 - Non-Polarity RS485 Communication
This is the preferred method of control with wired controller KSACN1001AAA (Not included)
Fig. 12 — Scenario 2
Scenario 3 - Full 24V Communication
This method allows for 24 communication between a 24V thermostat, the indoor unit and the outdoor unit.
Fig. 13 —Scenario 3
NOTE: For scenarios 2 and 3 - The use of shielded communication or thermostat wire is not required but is recommended
where separation from high voltage conductors cannot be maintained, or in areas with high electrical noise. The shield
and drain conductor must be grounded at the outdoor unit and stripped back and taped at the indoor unit. Grounding
at both ends results in an increase of noise transmitted onto the signal wires.
Outdoor Unit
RCGY1Y2BW W1W2EDHL
24V Thermostat
Indoor Unit Display Board
RCGY1Y2BWW1W2EDHL S1S2
S1 S 2RCY1Y2BWDL
Control
Board
ON
SW1
1 2 3 4
Refer to the wiring nameplate for the wiring method.
DO NOT connect 24V AC to S1-S2, as this will damage the
system.
WA R N I N G
RCY1Y2BW D L
Outdoor Unit
Indoor Unit Display Board
RC L GY1
Y1/Y2
BWW1W2EDH
S1 S2
S1 S 2
Wired
Controller
Wired
Controller
HA HB
HA HB
Control
Board
ON
SW1
1 2 3 4
Outdoor Unit
RCGY1Y2BW W1W2EDHL
24V Thermostat
Indoor Unit Display Board
RCGY1Y2BWW1W2EDHL S1S2
S1 S 2RCY1Y2BWDL
Control
Board
1 2 3 4
ON
SW1

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
11
WIRING DIAGRAMS
Fig. 14 — Wiring Diagram - All Models
Table 4 — Wiring Diagram - All Models
CODE CODE2 INDOOR UNIT MAINBOARD CONNECTION
CN5 5 output: 0-5VDC for water level switch connection
CN6 6 output: 5VDC for T2A, T2B (Temperature sensor)
CN9 9 output: 24VAC for 24V Interface
CN10 10 communication: 15VDC for 24V Interface
CN11 11 input: 230VAC High voltage
CN12 12 output: 24VAC for Heaters
CN15 15 output: 220VAC for ECM motor (fan)
CN18 18 output: 0V connection to ground
CN20 20 communication: 0-24VDC Low High voltage
CN22 22 output: 220VAC High voltage to transformer
CN29 29 output: 5VDC for T2 (Temperature sensor)
CN33 33 output: Normally open dry contact
CN34 34 output: 12VDC for ECM motor control
CN46 46 output: 5VDC for T1 (Temperature sensor)
CN43 43 output: 24VAC UVLED
CN23 23 output: Normally open dry contact - work
INDOOR UNIT
MAINBOARD
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
45789AB
 53
54 ~71 72~90 91 ~10 5 106 ~14 0 141 ~ 16 0
 16 1
Y/G
CN1 8
ALAR M
CN2 3CN3 3
WOR K
6
CN1 0
CN 5
T1
ECM
51NC
CDV21:tuptuO

M
4(3) 3
CN34
UVLED
OUTPUT
BLUE
RED
RED
CN 22
RED
TRAN S
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
12
ON
0~F 0~F 0~F 0~F
0~15 16~31 32~47 48~63
CN 9
NOTE:
reference the application’s manual.
1.The other switches should be set as
"Off" state from factory .
2.The specific use of the switches please
J1
CN2 9
T2
CN1 2
3
HEATER
2
CN 11
0
8
4
1
2
3
5
6
7
C
9
A
B
D
E
F
0~F ON~OF F ON~OF F FFO~NO
123
ON
4
SW 1
123
ON
4
SW 2
123
ON
4
SW 3
S3
ON~OF F
123
ON
4
SW 4
12
ON
S4
CODE
ECM
PART NAME
INDOOR ECM MOTOR
T1
T2
T2A
T2B
WIRING DIAGRAM
INDOOR COIL INLET TEMP.SENSOR
ROOM TEMP. SENSOR
COILTEMP> SENSOR
L1
INDOOR COIL OUTLET TEMP.SENSOR
L2
RED
BLAC K
2
NL
TO OUTDOOR UNIT
OR POWER
L and N :230VAC
WATER LEVEL
SWITCH
Output:5VDC
Output:5VDC
CAV022
:tuptuO
CN4 3
CN4 6
Output:24VAC
Output:5VDC
Output:15VDC
Output:24VAC
CAV022:tupt
uO
CAV42:tuptuO
JR1
CN 5
CN 4
CN 1
CN2
Remote
Control
ON/OF F
24V THERMOSTAT
CN9CN6 CN1 0 CN11
CONTR OLLE R
2 WIRE WIRE
4
48 5 PO RT
CN3
E Y X
To
Com m
CCM
.Bu s
CDV5
1+:tuptu
O
CD
V21+:tuptuO
CAV42:tuptu
OCAV4
2:tuptu
O
Output:+5VDC
CN7 CN1 4
Output:+15VDC Output:+12VDC
Output:24VAC Output:24VAC Output:24VAC Output:24VAC
3.The CN5/CN23/CN33 connects to left and right terminals.
Y/ G
NOTE:
1.The parts with a dotted line indicates
optional features.
2.Remove the short connector of JR1
when you use the "on-off" function.
3.Remove the short connector of J1
when using the "WATER LEVEL
SWITCH" function.
4. This symbol indicates the element
is optional, the actual shape prevails.
DRY CONTACT
ON~OF F
DRY CONTACT
CN6
CN21
Output:5VDC
2
2
Output:12VDC
S1 S2
CN20
COMMUNICATION
T O OUT DOOR UNIT
W1
DH
R C
L
G Y1
Y/Y2
W
B
W2
E/AU X
T2B
T2A
6
Electroni c
expansio n valv e
FOR SETTING NET ADDRESS
NETADDRESS
FOR SETTING POWER (DC MOTOR MODEL ONLY)
FACTORY
SETTING
FACTORY
SETTING
CODE
S1 +S2
CODE
24V THERMOSTATS SETTING
ENC1
CODE
CAPACITY
FACTORY
SETTING ACCORDING TO RELATED MODEL

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
12
REFRIGERANT LINES
General refrigerant line sizing
1. The outdoor units are shipped with a full charge of R410A refrigerant. All charges, line sizing, and capacities are based on runs of 25 ft. (7.6 m). For runs
over 25 ft. (7.6 m), consult the product data.
2. Minimum refrigerant line length between the indoor and outdoor units is 10 ft. (3 m).
3. Refrigerant lines should not be buried in the ground. If it is necessary to bury the lines, not more than 36 in. (914 mm) should be buried. Provide a
minimum 6 in. (152 mm) vertical rise to the service valves to prevent refrigerant migration.
4. Insulate the suction line. Use a minimum of ½ in. (12.7 mm) thick insulation. Closed-cell insulation is recommended in all long-line applications.
5. Special consideration should be given to isolating interconnecting tubing from the building structure. Isolate the tubing so that vibration or noise is not
transmitted into the structure.
6. For piping runs greater than 25 ft. (7.6 m), add refrigerant up to the allowable length as specified in the installation manual.
Refrigerant Coil Specifications
Table 5 — Refrigerant Coil Specifications
UNIT SIZE 18 24 30/36/48 60
DUCTED INDOOR COIL
Number of rows 3 4 5
Tube pitch (a)x row pitch (b) in 0.83x0.53
mm 21x13.37
Fin Spacing FPI 20
mm 1.3 1.3 1.3 1.3
Fin type Louvered
Fin Material Gold hydrophilic aluminum
Tube outside diameter inch 0.276
mm 7
Nominal Tube Wall mm (inch) 0.00945 (0.24)
Tube Enhancement (Yes/ No) Yes
Tube Material Aluminum
Coil length x height x width inch 16.34x13.23x1.58x2 16.34x21.5x2.11x2 16.34x21.5x2.63x2
mm 415x336x40.11x2 415*546*53.48*2 415*546*66.85*2
Face area ft
2
3 4.88 4.88
Number of circuits 6 10 14
Metering Device inch EEV
High Burst Pressure Psi (MPa) 550(3.79)
Low Burst Pressure Psi (MPa) 340(2.34)
Design (high/low) Burst Pressure Psi 550/340
Gas Pipe (size – connection type) In (mm) Ø3/4” (19) Ø3/4” (19) Ø3/4” (19) Ø7/8” (22)
Liquid Pipe (size – connection type) In (mm) Ø3/8” (9.52) Ø3/8” (9.52) Ø3/8” (9.52) Ø3/8” (9.52)

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
13
TROUBLESHOOTING
Error Display (Indoor Unit)
When the indoor unit encounters a recognized error, an error code appears (see Table 6).
Table 6 — Error Display (Indoor Unit)
For other errors: The display board may display a code or a code undefined by the service manual. Ensure the code is not a temperature reading.
Table 7 — Error Display on Two Way Communication Wired Controller
The other error codes displayed on the wire controller are the same from those on the unit.
Turn off all power supplies or disconnect all wires to avoid electric
shock. While checking indoor/outdoor PCB, please equip oneself with
anti-static gloves or wrist strap to avoid damage to the board.
WA R N I N G
Electricity remains in capacitors even when the power supply is off.
Ensure the capacitors are fully discharged before troubleshooting.
Please wait five minutes before attempting the service to the PCB.
WA R N I N G
DISPLAY ERROR INFORMATION SOLUTION
EH00 Indoor unit EEPROM parameter error Page 16
EL01 Indoor / outdoor unit communication error Page 17
EL16 Communication malfunction between adapter board and outdoor main board Page 32
EH03 The indoor fan speed is operating outside of the normal range (for some models) Page 22
EH60 Indoor room temperature sensor T1 is in open circuit or has short circuited Page 22
EH61 Evaporator coil temperature sensor T2 is in open circuit or has short circuited Page 22
EH62 Evaporator coil temperature sensor T2B is in open circuit or has short circuited Page 22
EH65 Evaporator coil temperature sensor T2A is in open circuit or has short circuited Page 22
ELOC Refrigerant Leakage Detection (for some models) Page 23
EH06 Communication error between indoor two chips --
EH0E Water-level alarm malfunction Page 24
EC07 The outdoor fan speed is operating outside of the normal range (for some models) Page 20
EC51 Outdoor unit EEPROM parameter error --
EC52 Condenser coil temperature sensor T3 is in open circuit or has short circuited Page 22
EC53 Outdoor room temperature sensor T4 is in open circuit or has short circuited Page 22
EC54 Compressor discharge temperature sensor TP is in open circuit or has short circuited Page 22
EC56 Evaporator coil outlet temperature sensor T2B is in open circuit or has short circuited (for free match indoor units) --
PC00 IPM malfunction or IGBT over-strong current protection Page 25
PC01 Over voltage or over low voltage protection Page 26
PC02 Top temperature protection of compressor or High temperature protection of IPM module Page 27
PC03 Low pressure protection (for some models) Page 28
PC04 Inverter compressor drive error Page 29
EC0d Outdoor unit malfunction Page 30
PC0L Low ambient temperature protection Page 30
FL09 Mismatch between the new and old platforms Page 32
DISPLAY MALFUNCTION OR PROTECTION SOLUTION
EH63 Communication error between wire controller and indoor unit ---

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
14
Quick Maintenance by Error Code
Review Tables 8 - 11 for common faulty parts associated with each error code.
Table 8 — Quick Maintenance by Error Code
Table 9 — Quick Maintenance by Error Code
PART REQUIRING REPLACEMENT ERROR CODE
EH 00 EL 01 EH 03 EH 60 EH 61 EH 62 EH 65 EL 0C EH 0E EC 53
Indoor PCB

x
Outdoor PCB
xxxxxxxx

Indoor fan motor
xxxxxxxxx
T1 sensor
xxxxxxxxx
T2 Sensor
xxxxxxxxx
T2B Sensor
xxxxxxxxx
T2A Sensor
xxxxxxxxx
T3 Sensor
xxxxxxxxxx
T4 Sensor
xxxxxxxxx

Reactor
xxxxxxxxx
Compressor
xxxxxxxxxx
Additional refrigerant
xxxxxxxxx
Water-level switch
xxxxxxxxx
Water pump
xxxxxxxxx
PART REQUIRING REPLACEMENT EC 54 EC 51 EC 5C EC 52 EC07/71/72/73 PC 00 PC 01 PC 02 PC 04 PC 03
Indoor PCB
xxxx x xxxxx
Outdoor PCB
  
Outdoor fan motor
xxxx  x  x
T3 Sensor
xxx  x xxxxx
TP Sensor
 xxx x xxxxx
Pressure sensor
xx  x x xxxxx
Reactor
xxxx x x  xxx
Compressor
xxxx x  xx  x
IPM module board
xxxx x  x
Low pressure protector
xxxx x xxxx 
Additional refrigerant
xxxx x xxxx 

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
15
Quick Maintenance by Error Code (Cont.)
Table 10 — Quick Maintenance by Error Code
Table 11 — Quick Maintenance by Error Code
NOTE: For certain models, the outdoor PCB can not be removed separately. In this case, the outdoor electric control box
should be replaced as a whole.
PART REQUIRING REPLACEMENT EL 16 EH 0BPC 06 PC 08/44/ 49 PC 0A PC 0F
Indoor PCB x

xxxx
Outdoor PCB

x

Outdoor fan motor xxx

x
T3 Sensor xxxx

x
TP Sensor xx

xxx
Pressure sensor xxxxxx
Reactor xxx

x

Compressor xxxxxx
IPM module board xxx

xx
Data adapter board

xxxx
High pressure valve assembly xx

xxx
High pressure protector xxxxxx
Low pressure protector xxxxxx
Additional refrigerant xx

x

x
PART REQUIRING REPLACEMENT PC 41 PC 43 PC 10/11/12 PC 30 PC 31 PC 40
Indoor PCB xxxxxx
Outdoor PCB

Outdoor fan motor xxx

xx
T3 Sensor xxxxxx
TP Sensor xxxxxx
Pressure sensor xxxxxx
Reactor xx

xxx
Compressor x

xxxx
IPM module board xx

xx

Data adapter board xxxxxx
High pressure valve assembly xxxxxx
High pressure protector xxx

xx
Low pressure protector xxxx

x
Additional refrigerant xxxx

x
Electric control box xxxxx


40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
16
DIAGNOSIS AND SOLUTION
EH00 - EEPROM Parameter Error Diagnosis and Solution
Description: Indoor or outdoor PCB main chip does not receive feedback from the EEPROM chip.
Recommended parts to prepare:
• Indoor PCB
• Outdoor PCB
Troubleshooting and Repair:
NOTE: The priority is EH00 followed by EC51.
Shut oīthe power and turn it on 2
minutes later.
Is it sƟůů
displaying the
error code? The unit is operaƟng normally.No
Replace the indoor main PCB (EH 00)/
outdoor main PCB (EC 51)
Yes

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
17
DIAGNOSIS AND SOLUTION (CONT.)
EL01 - Indoor and Outdoor Unit Communication Error Diagnosis and Solution
Description: Indoor unit can not communicate with the outdoor unit.
Recommended parts to prepare:
• Signal wires
• Magnet ring
• Indoor PCB
• Outdoor PCB
Troubleshooting and Repair:
XYE Communication:
Power o, then restart the unit
2 minutes later.
Use a shield cable grounding.
No
Yes
.
Correct the connection .
No
Yes
Yes
Replace the signal wire.
Yes
Pull out and re-insert.No
Replace the outdoor main PCB.
Check whether the signal wire is
shield cable or whether the
shield cable is ground.
Check whether the wire has the correct
polarity; P to P, Q to Q, or E to E.
Check whether the signal wire is broken.
Check whether the signal wires
are inserted on the PCB rmly.
Check whether there is any interference.
Are there too many lamps, power transformers?
Is the signal wire too long?
Yes
No
No
Replace the indoor main PCB.
Is the error resolved?
Yes
No
Remove the interference or
add a magnet ring on the power wire.

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
18
DIAGNOSIS AND SOLUTION (CONT.)
(S) Current Loop Communication:
NOTE: For certain models, outdoor PCB could not be removed separately. In this case, the outdoor electric control box should
be replaced as a whole.
Does the error code
disappear?
Power off, then restart the unit af ter 2
minutes.
Measure the DC voltage between N/L2
and S (Black pin to S , Red pin to N/L2).
The value is fixed and close
to 0
The value is alt ernative
from negative to positive
(correct value)
The value is alw ays posit ive
Check t he w irin g connection
bet ween in door and o ut door
unit, are t hey goo d?
Check t he w irin g connection
from o utd oor termin al t o
outdoor PCB and wiring
bet ween PCBs if t here is
mo re t han 1 PCB
Check t he w irin g connection
from ind oor term in al t o ind oor
PCB, are t hey goo d?
Check if t he pow er LED is
on?
Yes
Yes
Unplug all the high voltage
components connected t o main
PCB such as 4 way valve, heater,
AC f an one by one to check their
resist ance. Is there any component
short circuit?
Unplug electronic expansion valve.
Check if power LED ison?
No
No
Check t he AC volt age of L, N
output t o IPM board, is it same
as pow er input?
Check t he DC 5V, 12V
from IPM board t o main
PCB, are t hey normal?
Unplug all the high voltage
components connected t o main
PCB such as 4 way valve, heater,
AC f an on e by one t o check th eir
resist ance. Is there any componen t
short circuit?
Yes
No
Unplug electronic expansion valve.
Check if t he DC 5V, 12V to m ain
PC B ar e O K
Replace short-circuited
component and main
PCB
Replace coil of elect ronic
expansion valve
Replace o ut door PCB
Replace short-circuited
component and outdoor
PCB
Yes
Yes
Yes
Yes
Replace main PCB
No
Yes
No
Replace IPM board
No
Repalce indoor PCB
So l ve d
Correct the connection or
change w ires
No
No
Yes
For units with main PCB and IPM board
both
For units with only one
PCB
No

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
19
REMARKS:
• Use a multimeter to test the DC voltage between the 2 port (or S or L2 Terminal) and the 3 port (or N or S Terminal) of the outdoor unit.
• The red pin of the multimeter connects with the 2 port (or S or L2 port) while the black pin is for the 3 port (or N or S Terminal).
• When the unit is normal running, the voltage is moving alternately as positive values and negative values.
• If the outdoor unit malfunctions, the voltage remains a positive value.
• If the indoor unit malfunctions, the voltage does not change.
• Use a multimeter to test the reactor resistance which does not connect with the capacitor.
• The normal value should be around zero ohm. Otherwise, the reactor has malfunctioned.
NOTE: The figures and values are for reference only, actual condition and specific value may vary.
S and N
or
L2 and S
or
2 and 3

40MUAA: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
20
DIAGNOSIS AND SOLUTION (CONT.)
EH03 / EC07 - Fan Speed Is Operating Outside of Normal Range / EC 71 Over Current Failure of
Outdoor DC Fan Motor / EC73 Zero-speed failure of outdoor DC fan motor Diagnosis and Solution
Description: When the indoor / outdoor fan speed operates at too low or too high a speed for a certain time, the unit ceases
operation and the LED displays the failure.
Recommended parts to prepare:
• Connection wires
• Fan assembly
•Fanmotor
•PCB
Troubleshooting and Repair:
NOTE: For certain models, the outdoor PCB cannot be removed separately. In this case, the outdoor electric control box should
be replaced as a whole.
YES
Power o. Restart the unit after 2 minutes.
Is it within normal parameters?
Replace the fan motor.
Does a problem remain? The unit is operating normally.NO
Shut o the power supply.
Rotate the fan by hand.
YES
Does it turn easily? Inspect the unit for an obstruction and remove.NO
Check the fan motor wiring.
YES
Is it improperly wired? Ensure the proper connections.
Measure the voltage for
the fan motor from the PCB.
YES
Replace the main PCB.NO