Troubleshooting For Normal Malfunction - Friedrich MWM09Y1J Service & Parts Manual

TROUBLESHOOTING

Troubleshooting for Normal Malfunction

Possible Causes
Air Conditioner will not start up
No power supply, or poor connection for
power plug
"Wrong wire connection between indoor
unit and outdoor unit,
or poor connection for wiring terminals"
Electric leakage for air conditioner
Model selection for air switch is improper
Malfunction of remote controller
Poor Cooling (Heating) for Air Conditioner
Set temperature is improper
Rotation speed of the IDU fan motor is set
too low
Filter of indoor unit is blocked
Installation position for indoor unit and
outdoor unit is improper
Refrigerant is leaking
Malfunction of 4-way valve
Malfunction of capillary
108
Discriminating Method (Air conditioner
Status)
After energization, operation indicator isn't
bright and the buzzer can't give out sound
Under normal power supply circumstanc-
es, operation indicator isn't bright after
energization
After energization, room circuit breaker
trips off at once
After energization, air switch trips off
After energization, operation indicator is
bright, while no display on remote control-
ler or buttons have no action.
Observe the set temperature on remote
controller
Small wind blow
Check the filter to see it's blocked
Check whether the installation postion is
proper according to installation require-
ment for air conditioner
Discharged air temperature during cooling
is higher than normal discharged wind
temperature; Discharged air temperature
during heating is lower than normal dis-
charged wind temperature; Unit's pressure
is much lower than regulated range
Blow cold wind during heating
Discharged air temperature during cooling
is higher than normal discharged wind
temperature; Discharged air temperature
during heating is lower than normal dis-
charged wind temperature; Unit't pressure
is much lower than regulated range. If
refrigerant isn't leaking, part of capillary is
blocked
Troubleshooting
Confirm whether it's due to power failure.
If yes, wait for power recovery. If not, check
power supply circuit and make sure the
power plug is connected well.
Check the circuit according to circuit
diagram and connect wires correctly. Make
sure all wiring terminals are connected
firmly
"Make sure the air conditioner is grounded
reliably
Make sure wires of air conditioner is con-
nected correctly
Check the wiring inside air conditioner.
Check whether the insulation layer of
power cord is damaged; if yes, place the
power cord."
Select proper air switch
Replace batteries for remote controller
Repair or replace remote controller
Adjust the set temperature
Set the fan speed at high or medium
Clean the filter
Adjust the installation position, and install
the rainproof and sunproof for outdoor unit
Find out the leakage causes and deal with
it. Add refrigerant.
Replace the 4-way valve
Replace the capillary