Troubleshooting - Barnstead 47900 Operation Manual

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 malfunc-
tion. Then proceed to the possible causes category and take necessary corrective action.
Problem
Cycle light does not
illuminate.
Furnace does not heat.
Possible Causes
The furnace is not
connected to power supply.
Incorrect power source.
ON and OFF power switch
defective.
Defective cycle light.
Door switch malfunction.
No power.
Defective electrical hookup.
Thermocouple has oxidized and Replace thermocouple.
opened the circuit.
Controller malfunction.
Heating elements
burned out.
Door switch malfunction.
Defective OTP relay.
Defective solid state relay.
Corrective Action
Reconnect furnace to power
supply.
Connect to correct power
source.
Replace power switch.
Replace cycle light.
Realign or replace furnace
door safety switch.
Check power source and
fuses or breakers.
Repair electrical hookup.
Replace controller.
Replace defective elements.
Realign or replace door safety
switch.
Replace relay.
Replace relay.
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