7.0
Fault Analysis
A.
Furnace Does Not Heat Up
1.
The
HEAT
light(s)
are ON.
An ohm meter applied
to the element circuit
shows an open circuit.
A heating element has failed.
2.
The
HEAT
light(s)
are OFF.
The controller shows a
very high temperature
or a code such as S.br.
The thermocouple has broken or
has a wiring fault.
The controller shows a
low temperature.
The door switch may be faulty or
need adjustment.
The thyristor fuse may have
blown.
The power thyristor could be
failing to switch on due to internal
failure, faulty wiring from the
controller, or fault controller.
There are no lights
glowing on the
controller.
Check the supply fuses and any
fuses in the product control
compartment.
The controller may be faulty or
not receiving a supply due to a
faulty switch or a wiring fault.
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