Friedrich MRM09Y1J, Service & Parts Manual

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108 PB
TROUBLESHOOTING
Troubleshooting for Normal Malfunction
Possible Causes Discriminating Method (Air conditioner
Status) Troubleshooting
Air Conditioner will not start up
No power supply, or poor connection for
power plug
After energization, operation indicator isn’t
bright and the buzzer can't give out sound 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.
"Wrong wire connection between indoor
unit and outdoor unit,
or poor connection for wiring terminals"
Under normal power supply circumstanc -
es, operation indicator isn't bright after
energization
Check the circuit according to circuit
diagram and connect wires correctly. Make
sure all wiring terminals are connected
firmly
Electric leakage for air conditioner After energization, room circuit breaker
trips off at once "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."
Model selection for air switch is improper After energization, air switch trips off Select proper air switch
Malfunction of remote controller After energization, operation indicator is
bright, while no display on remote control
-
ler or buttons have no action.
Replace batteries for remote controller
Repair or replace remote controller
Poor Cooling (Heating) for Air Conditioner
Set temperature is improper
Observe the set temperature on remote
controller Adjust the set temperature
Rotation speed of the IDU fan motor is set
too low Small wind blow Set the fan speed at high or medium
Filter of indoor unit is blocked Check the filter to see it's blocked Clean the filter
Installation position for indoor unit and
outdoor unit is improper Check whether the installation postion is
proper according to installation require
-
ment for air conditioner
Adjust the installation position, and install
the rainproof and sunproof for outdoor unit
Refrigerant is leaking 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
Find out the leakage causes and deal with
it. Add refrigerant.
Malfunction of 4-way valve Blow cold wind during heating Replace the 4-way valve
Malfunction of capillary 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
Replace the capillary