Service manual

M411433 15

Section 3 Troubleshooting

To reduce the risk of electric shock, fire, explosion, serious injury or death:

• Disconnect electric power to the tumbler before servicing.

• Close gas shut-off valve to gas tumbler before servicing.

• Close steam valve to steam tumbler before servicing.

• Never start the tumbler with any guards/panels removed.

• Whenever ground wires are removed during servicing, these ground wires must be

reconnected to ensure that the tumbler is properly grounded.

W002

WARNING

6. IGNITER GLOWS, FLAME SENSOR OPENS BUT NO IGNITION - GAS MODELS

(White Rodgers Glow-bar Ignition)

7. BURNER IGNITES AND GOES OUT REPEATEDLY - GAS MODELS

(Glow-Bar Ignition)

POSSIBLE CAUSE TO CORRECT

Insufficient gas supply. • Is manual shut-off valve in full open position? Check gas

pressure.

Gas flow, but no ignition. • Gap between igniter and burner must be 1/8 – 1/4 inch.

No gas flow through gas valve. • Check for 80 – 120 Volts between red and white wires on

gas valve.

• If correct voltage is present and redundant coil does not

click open, replace complete gas valve.

• If correct voltage is not present, replace diode logic board.

• If correct voltage is present and redundant coil clicks

open, check for 40 – 60 Volts across the purple wires on

the main coil after the igniter cycles off.

• If voltage is present and main coil does not click open,

replace main coil.

• If no voltage is present, replace diode logic board.

POSSIBLE CAUSE TO CORRECT

Burner heat not holding sensor contacts open. • Replace sensor.

Insufficient gas pressure. • Check gas supply and pressure. A low flame will not

maintain radiation to sensor.

Burner ports plugged or dirty. • Check burner tubes for build-up.

Improper or inadequate exhaust system or make-up

air.

• Refer to Installation Manual (supplied with tumbler) for

exhaust and make-up air requirements.

Inoperative high limit thermostat. • Test thermostat and replace in inoperative.

Improper orifices. • Tumbler is equipped for type of gas specified on serial

plate. If orifices are different from that specified on serial

plate, obtain and install proper orifices.