Confirm operating
conditions
no
yes
yes
no
No need to replace mainboard. The fault may
be caused by power supply
yes
no
Does the same
fault occur before?
yes
no
No need to replace mainboard. Contactor
wasn't in good contact
No need to replace mainboard. (Check
operating status in details, e.g. TIMER feature,
supply failure, thunder storm, interference from
other appliances, etc.) Explain causes of fault
to user.
1.Is supply voltage acceptable?
2.Is temperature setting correct? (e.g. too high)
3.Is system in TIMER mode?
4.Is user aware of product features, etc.
Check the system thoroughly,
e.g. technical data of
components when power-off,
and voltage and current of
check points when power-on
Disconnect contactor
and reconnect it.
(check if fuse or
varistor is broken.)
Does the same
fault occur before?
Switch off air conditioner
temporarily.
Switch
on air conditioner again
after 1 minute
Does the same
fault occur before?
yes
no
Switch on air
conditioner
Is the feature not
available for present
product?
Fault confirmation
Explain product
features to user
For example: no cooling, etc.
14)
Troubleshooting (before replacement of PCB)
Service call
Model: AD182ALERA AD362AHERA
Commercial Air Conditioner
46