9-2. Air conditioner does not operate.
9-2-1. Circuit breaker trips (or fuse blows).
A. When the circuit breaker is set to ON, it is tripped soon. (Resetting is not possible.)
There is a possibility of ground fault.
Check insulation resistance.
If resistance value is 2MΩ or less, insulation is defective ("NO").
Power
supply
WARNING
*
Set circuit breaker to OFF.
1 Remove both power supply wires
and inter-unit wires from terminal
plate in outdoor unit.
Measure insulation resistance
•
of outdoor unit.
2 Remove inter-unit wires from
terminal plate in indoor unit.
Measure insulation resistance
•
of indoor unit.
B. Circuit breaker trips in several minutes after turning the air conditioner on.
There is a possibility of short circuit.
•
Check capacity of circuit breaker.
Capacity of circuit breaker is
suitable.
Measure resistance of outdoor fan
•
motor winding.
•
Measure resistance of compressor
motor winding.
Circuit
breaker
Ground
NO
Inter-unit
Outdoor
power wiring
unit
1
1
1
2
4
5
NO
NO
Replace with suitable
one (larger capacity).
29
Indoor
unit
2
1
2
4
5
Insulation of
outdoor unit
is defective.
Measure insulation
•
resistance of electrical
parts in outdoor unit.
Insulation of
indoor unit
is defective.
Measure insulation
•
resistance of electrical
parts in indoor unit.