Service manual

PART IV TROUBLESHOOTING - NO POWER
E-38
ENGLISH
Why does the fuse keep damaging?
After replacing the blown fuse with a new one, try to operate the unit but new fuse is still blown out with unknown reasons.
To fix this problem, you have to spend time to check all the electrical wires in the unit. At first, check if the electrical wire
casing is damaged. The damaged wires will cause a short circuit between them or the damaged Live line may touch the unit
metal casing to create a short circuit. You can use ohmmeter to check if the wires are short circuited. If you are sure there is
no any damaged electrical wires you need to check other causes.
1. Check the interlock switch
Unplug all the connections from the main circuit board and try to start the unit. If the fuse is still blown, indicating that the
interlock switch is problem. Please replace the interlock switch. If the fuse is OK, you need to go ahead to check parts (see
below picture).
2. Check the main circuit board
Plug in the interlock switch connection to the main circuit board and try to start the unit. If the fuse is blown, the main circuit
board is problem. You need to replace the main circuit board. If the fuse is OK, please go ahead to check parts (see below
picture).
3. Check the main circuit board transformer
Plug in the main circuit board transformer connection to main circuit board and try to start the unit. If the fuse is blown, the
main circuit board transformer has problem. You have to replace the main circuit board transformer. If the fuse is OK, please
go ahead to check other parts (see below picture).
4. Check the power supply transformer
Plug in the power supply transformer connection to the main circuit board and try to operate the unit. If the fuse is blown,
the power supply transformer has problem. Please replace the power supply transformer. If the fuse is OK, you have still go
ahead to check next part (see below picture).
5. Check the UV lamp ballast
Plug in the UV lamp power cord connection to the main circuit board and operate the unit. If the fuse is still blown, the
ballast has problem. You need to replace the ballast. If the fuse is OK, you will go ahead to check the fan motor.
6. Check the fan motor
Finally, plug in the fan motor connection to the main circuit board and try to start the unit. If the fuse is blown, the fan motor
has problem, you will need to replace the fan motor.
1. To check interlock switch,
unplug all the connections from
the main circuit board and start
the unit.
2. To check the main circuit board,
plug in the interlock switch
connection to the main circuit board
and operate the unit.
3. To check the main circuit board
transformer, connect the
transformer to the main circuit
board and operate the unit.
5. To check the UV lamp ballast,
plug in the UV lamp connection to
the main circuit board and operate
the unit.
6. To check the fan motor, connect
the fan motor connection to the
main circuit board and try to start
the unit.
4. To check the power supply
transformer, plug in transformer
connection to the main circuit
board and try to run the unit.