263 - INVERTER ERROR
Is the voltage supply OK?
YES
YES
YES
Is the high pressure during
operation OK?
Are the checks of the insulation
resistance and the coil's
resistance (0.4 ohm or greater at
25 °C) for the compressor OK?
Action.
Open the service valves.
Are the service valves open?
Check the amount of refrigerant.
Check the refrigerant circuit.
Replace the compressor.
NO
NO
NO
NO
YES
- Is the air circulation at the
outdoor unit obstructed?
- Is the installation space
sufficient?
- During cooling, does the fan
motor run?
- Are the service valves fully
open?
- Is the filter blocked?
- Are the low pressure transmitter
and the suction gas sensor OK?
- Does the compressor sound
different than usual?
Check the power transistor *
Temporary surge on incoming
supply may have caused the
alarm.
YES
Is the power transistor damaged
or burned?
Replace the inverter board PWB2
Is there a short-circuit between the
terminals on the power transistor?
Does the current between the
phases to the compressor differ by
10% or more?
NO
NO
YES
YES
YES
NO
* See page
for checking power transistor.
NIBE AMS10
Chapter 6 | Troubleshooting
52
