35
8. Troubleshooting
Fault diagnosis
Symptom
Cause
Remedy
Breaker for motor trips in
a short time
Short circuit
Detect the location of short-
circuit, and rewire
Overload operation
Remove the cause of overload
Defective motor
Replace or repair the motor
Too large moving friction
of windowpane
Insufficient lubrication of pulley
Apply grease to the pulley and
guide rail
Wire is off its pulley
Engage the wire into groove of
pulley
Broken balance weight wire
Replace the wire
Reduced discharged air
quantity
Clogged pre-filter
Clean or replace the pre-filter
Clogged part filter
Replace the part filter
Drift of volume damper angle
Re-adjust the volume damper
Reduced air flow caused by
increased pressure loss due to
built-up of particles in the duct
Clean the inside of duct to
remove particles
Outside air enters the duct
because of broken fan duct or
loosened attaching bolt
Repair the broken section
Re-tighten the bolt and insert
a spring washer
Defective exhaust blower
Repair or replace with new one
Fluorescent light does
not illuminate
The breaker does not turn on
Turn the breaker on
Deteriorated fluorescent light
Replace the fluorescent light
No electricity to the
outlet
The breaker does not turn on
Turn the breaker on
Discontinued wire
Re-connect the discontinuity
Exhaust blower does not
stop when the stop key
is pushed
The delay timer is activating
It stops when the predetermined
time interval elapses, because
the delay timer is activating
Defective key
Replace the key and circuit
board as an assembly