Thermo Products GDM1-80N, GMD1-60N service manual Vii. Troubleshooting

All installations and services must be performed by qualified service personnel.

VII. TROUBLESHOOTING

THIS SECTION IS ONLY TO BE PERFORMED BY TRAINED, QUALIFIED SERVICE PERSONNEL, AND NOT BY THE FURNACE OWNER.

NOTICE: BEFORE TROUBLESHOOTING, FAMILIARIZE YOURSELF WITH THE START UP AND CHECKOUT PROCEDURE. ALL INSTALLATION AND SERVICES MUST BE PERFORMED BY QUALIFIED HEATING CONTRACTORS

When testing electrical equipment, always follow standard electrical procedures and precautions.

Note – check diagnostic code through view port prior to removal of door.

1.Check for line voltage (110-120VAC) to the furnace. If there is no line voltage applied to the furnace, check that disconnecting switch is “on”, fuses or circuit breakers have not blown or tripped.

2.Make sure thermostat is “calling for heat”.

3.Check for adequate fuel supply and pressure. Are all the fuel shutoff valves open?

4.To assist you in troubleshooting this furnace, it is equipped with an integrated ignition control with diagnostics. These diagnostics evaluate what malfunction the control system has experienced and will activate a flashing light on the control in different sequences to help pinpoint the failure.

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