
10 Troubleshooting
Troubleshooting procedure
SMGB0091 rev.2 - 11/2015
216
Phenomenon
Cause
Check item
Action
(Turn OFF the main switch)
Decrease of
discharge gas
superheat
Refrigerant cycle is different from the electrical
system
Check refrigerant cycle
and the electrical system
Repair wiring
Overcharged refrigerant
Measure pressure
Correctly charge refrigerant
Faulty expansion valve
Check expansion valve
(*1)
Replace expansion valve if
faulty
Faulty PCB
Fault
Replace PCB and check
operation
Replace PCB if faulty
Disconnected wires for
expansion valve control
Check connections.
Repair wiring connections
Faulty discharge gas
thermistor
Fault
Measure resistance.
Replace thermistor if faulty
Incorrect mounting
Check mounting state.
(See
Alarm Code 08
)
Correctly mount thermistor.
Incorrect connection
Check connections.
Remove looseness,
replace connector or repair
connections.
Faulty RASC fan motor
Measure coil resistance
and insulating resistance
(*2)
Replace RASC fan motor if
faulty.
?
N O T E
“10.4.4 Checking procedure for the electronic expansion valve for indoor and RASC units”
• (*2): When the alarm code “07” is indicated, the RASC fan motor may be damaged. Ensure that fan motor is checked according to the
section
“10.4.3 Fault diagnosis of fan motor”
.