Symptom-based Troubleshooting
12
1. Symptom-based
Troubleshooting
Symptom
Supposed Cause Countermeasure
1 The system does not start
operation at all.
Blowout of
fuse(s)
Turn OFF the power
supply and then
replace the fuse(s).
Cutout of
breaker(s)
• If the knob of any
breaker is in its
OFF position,
turn ON the
power supply.
• If the knob of any
circuit breaker is
in its tripped
position, do not
turn ON the
power supply.
Power failure
After the power
failure is reset,
restart the system.
2 The system starts operation but
makes an immediate stop.
Blocked air inlet or outlet
of indoor or outdoor unit
Remove
obstacle(s).
Clogged air
filter(s)
Clean the air
filter(s).
3 The system does not cool or
heat air well.
Blocked air inlet or outlet
of indoor or outdoor unit
Remove
obstacle(s).
Clogged air filter(s) Clean the air filter(s).
Enclosed outdoor unit(s) Remove the enclosure.
Improper set
temperature
Set the temperature to
a proper degree.
Airflow rate set to
"LOW"
Set it to a proper
airflow rate.
Improper direction
of air diffusion
Set it to a proper
direction.
Open window(s) or door(s) Shut it tightly.
[In cooling] Direct sunlight
received
Hang curtains or
shades on windows.
[In cooling] Too many persons
staying in a room
The model must
be selected to
match the air
conditioning load.
[In cooling] Too many heat sources
(e.g. OA equipment)
located in a room
ON
OFF
Knob
Tripped
Circuit breaker
