Desa DNV25NB, DNV40NB installation manual Observed Problem Possible Cause

OWNER’S MANUAL

TROUBLESHOOTING

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OBSERVED PROBLEM POSSIBLE CAUSE REMEDY

Ignition failures	1. Glo bar will not glow - with blower run-
	ning and microswitch engaged

2. Glo bar glows but burner will not come on

3. Glo bar operating and gas valve open- ing but burner will not light

4. If the ignitor remains on after main burner ignition or the valve chatters, re- verse the 120-volt A.C. connections at the wall receptacle

1.Check the following:

A.Check for 24 volts A.C. across yellow and orange wires at ignition control. If no volt- age, check microswitch and limit switch for circuit completion as well as wiring and wir- ing connections

B.Voltage present across yellow and orange wires, check for 120-volt input to ignition control across red and blue wires. If no voltage, check wiring all the way back to power supply

C.120 volts present across red and blue wires, check for 120 volts across the two white wires at ignition control. If no voltage, replace igni- tion control

D.Voltage present across the two white wires, check wiring and wire connections to glo bar

E.If wiring and wire connections okay, replace glo bar. (Glo bar broken)

2.A. Check for voltage (24 volts A.C.) at valve 40 seconds after glo bar begins to glow. If voltage present but valve not opening, replace valve

B.If no voltage at valve, check brown wire at ignition control for continuity and good con- nection

C.If wire and wire connections okay, replace ignition control

3.A. Check gas flow through burner. If no gas is coming through burner, check for obstruc- tion in gas line, main burner orifice, or main burner

B.If thermostat okay, check for 24 volt A.C. circuit completion across yellow and orange wires at ignition control. If no voltage, check for circuit completion through limit switch and microswitch

C.If voltage is present at ignition control across yellow and orange wires yet burner contin- ues to go off, replace ignition control

4.A. If polarity is okay yet burner continues to go off, check thermostat to be sure it is still com- pleting the valve circuit. If not, check for excessive amp draw in valve circuit

B.If thermostat okay, check for 24 volt A.C. circuit completion across yellow and orange wires at ignition control. If no voltage, check for circuit completion through limit switch and microswitch

C.Voltage present at ignition control across yellow and orange wires yet burner contin- ues to go off, replace ignition control

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