Thermo Scientific F30400, Installation And Operation Manual

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Thermo Scientific Large Tabletop Muffle
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Troubleshooting
The Troubleshooting section is intended to aid in defining and correcting possible service problems.
When using the chart, select the problem category that resembles the malfunction. Then proceed to
the possible cause’s category and take necessary corrective action.
Problem Probable Causes Corrective Action
Cycle light on the
display does not
illuminate.
The furnace is not connected to power supply. Check furnace connection to power
source.
ON and OFF power switch is defective. Replace power switch.
Door switch defective. Realign door strike or replace door safety
switch.
Incorrect power source. Check power source.
Defective circuit breaker. Replace circuit breaker.
The furnace does not
heat.
No power. Check power source and fuses or breakers.
Defective electrical hookup. Repair electrical hookup.
Thermocouple has oxidized and opened the
circuit. Replace thermocouple.
Controller malfunction. Contact customer service.
Two or more heating elements burned out. Replace defective elements.
Door switch malfunction. Realign door strike or replace door safety
switch.
Defective safety relay. Replace safety repay.
Defective solid state relay (SSR). Replace SS relay.
Slow heatup.
Low line voltage. Install line of sufficient size and proper
voltage (Isolate furnace from other
electrical loads).
Heavy load in chamber. Lighten load in chamber to allow heat to
circulate.
Wrong heating element. Install proper element.
One or more heating elements are burned out. Replace burned out elements.
Wired improperly. Check wiring diagram for correct wiring of
your furnace.