Module Protection Handling Method - Toyotomi GAN GAG A180IV Service Manual

Module protection
Handling method:
Normal
Temperature of power module is too high,
which causes overheating protection
Confirm the setting status of outdoor unit (cooling)
Confirm if outdoor fan motor is running; unplug the
three connecting wires between U, V, W of compressor
and power module. Turn on the unit to see if outdoor
fan runs normally (about 1 minute)
Measure the voltage of outdoor
fan connector
No voltage
Replace the mainboard
of outdoor unit
Check if the voltage between power module P and N is too low and
if the current is too high. In normal condition, voltage between P and
N should be about 320V.
Protection is still displayed
Normal
Outdoor fan stops
Normal voltage
Replace the fan
motor
Check power supply circuit of outdoor unit (if PTC resistance
rectifying bridge, reactor, capacitance etc. is ok).
Check if radiating paste is spread
evenly or radiating sticker is stuck
well; if screws of power module
is tightened
Poor radiation, heat exchanger
is dirty
Confirm if there is voltage output and balance of
Outdoor fan runs
voltage between any two phases of U, V and W.
Yes
Whether module type
is correct
Abnormal
Replace the module
with correct type
Normal
Whether cylinder of
compressor is stuck
If the unit runs normally after connected
with the new compressor for trial run, the
cylinder of original compressor is stuck
44
Abnormal
Reinstall power module and
re-spread radiating paste or
stick radiating sticker on the
radiator of power module.
Remove obstructions
and clean
Replace the power module
Normal
Measure the three-phase
resistance of compressor
Replace the
compressor
No
Abnormal