JEM ZR12-DMX, Service Manual

Page: 28 / 29

HEATER PROBLEMS
Is power getting through
the thermal trip?
(check 240V / 110V)
THERMAL TRIP
FAULT – RESET /
REPLACE
Is power getting to the
thermal trip?
(check 240V / 110V)
See PCB
PROBLEMS
Disconnect power and remove power loom from element connectors
Is power getting to the heater?
(check 240V / 110V)
Measure across the elements for continuity and check for earth leaks
Normal Ohms reading?
OPEN CIRCUIT
HEATER -
REPLACE
See PCB
PROBLEMS
Earth leakage?
See PCB
PROBLEMS
OPEN CIRCUIT
HEATER -
REPLACE
Is the heater heating?
Overheating
CHECK
CALIBRATION
Check thermocouple
OK?
REPLACE
HEATER
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO