14
Table 7 — Troubleshooting
LEGEND
ERROR
MODE/STATUS
POSSIBLE CAUSES
POSSIBLE SOLUTIONS
E0
EEPROM Error
(Data Storage)
Chip or Main Board 1 damage
Replace Main Board 1.
E1
PFC protection
PFC board damage
Replace PFC board.
E2
Communication error between
outdoor and indoor unit
Power OFF on indoor or outdoor unit
Turn the power ON for indoor or outdoor unit.
Control cable of wrong type
Use shielded cable and provide proper grounding.
Incorrect signal wire polarity
Reconnect signal wires with correct polarity.
Signal wire continuity broken
Replace the signal wire.
Main Board 1 damage
Replace Main Board 1.
E3
Communication error between
Main Board 1 and Main Board
2
Main Board 2 faulty or damaged (LED
flashing)
Replace Main Board 2.
Improper voltage between ports P and N
on IPM
Replace IPM. Correct voltage is 277 v to 345 v.
Loose connection between CN1 port on
Main Board 2 and IPM
Reconnect or tighten the connection between CN1 ports.
E4
Condenser temperature sen-
sor (T3 & T4) malfunctioning
Loose connection at port on PC board
Tighten the connections at port on PC board.
Sensor is short-circuited
Using multimeter, measure resistance of the sensor. If the
resistance is
100 ohms, change the sensor.
E5
Outdoor unit voltage
protection
Improper voltage
Voltage measurement between L1 and L2 should be 172 v
to 265 v.
Filter board may be damaged due to
improper voltage
Replace filter board.
E6
DC fan motor (outdoor unit)
malfunctioning
Incorrect fan motor wiring
Correct fan motor wiring as per wiring diagram.
Improper supply voltage between fan
motor red and black terminals
Voltage should measure between 277 v and 354 v during
standby state. If not, replace the PFC.
Improper voltage between fan motor
white and black terminals
Voltage should measure 15V during standby state. If not,
replace the IPM.
Improper voltage between fan motor yel-
low and black terminals
Voltage should measure
2.4 v. If not, replace fan motor.
E7
Heating mode at high ambient
temperature
Call for heating when ambient tempera-
ture is above 80 F
Switch the heating mode to cooling.
P0
Radiator high temperature
protection
Sensor is short-circuited
Using multimeter, measure resistance of sensor. If the
resistance is
100 ohms
change the sensor.
Radiator is not connected securely
Connect the radiator securely.
Main Board 1 damage
Replace Main Board 1.
High outdoor ambient temperature
Check operating range of the outdoor unit.
P1
High pressure protection
Incorrect or loose wiring between high
pressure switch and main control board
Correct or tighten wiring between high pressure switch and
main control board per wiring diagram.
Broken or faulty high pressure switch
Short the high pressure switch terminal. If the system runs
normally, replace the high pressure switch.
High outdoor ambient temperature
Check the operating range of the outdoor unit.
P2
Low pressure protection
Incorrect or loose wiring between low
pressure switch and main control board
Correct or tighten wiring between as per wiring diagram.
Broken or faulty low pressure switch
Short the low pressure switch terminal. If the system runs
normally, replace the low pressure switch.
Low outdoor ambient temperature
Check the operating range of the outdoor unit.
Lack/loss of refrigerant
Check for leaks.
Clogged strainer
Replace strainer.
P3
Outdoor unit current protec-
tion (>30 A)
Ambient temperature higher than system
rating
Check ambient temperature. If higher than system rating,
stop the system and wait for ambient temperature to drop.
Short cycling of air around/over con-
denser
Remove any object blocking proper cycling of air around/
over condenser.
Accumulation of dirt and dust on con-
denser coil
Clean condenser coil to increase heat transfer.
Clogged refrigerant piping
Remove refrigerant from the system, flush the system with
nitrogen to remove foreign particles, evacuate and
recharge.
P4
High compressor discharge
temperature protection
Lack/loss of refrigerant
Check for leaks.
Incorrect wiring between compressor dis-
charge and PC board
Correct wiring as per wiring diagram.
Sensor is short-circuited
Using multimeter, measure resistance of the sensor. If the
resistance is
100 ohms, change the sensor.
IPM
— Intelligent Power Module
PC
— Process Control
PFC
— Power Factor Correction
