TROUBLE SHOOTING
DIRECTIONS:
Find the specific
symptom.
refer to the
Sequence of component Operation Guide.
Check the components listed with a
voltmeter
for proper operation as described. Replace any com-
ponents not operating correctly.
Fan will not start when ON switch & thermostat are ON.
• Check sequences 1 through 8 (Page 9).
Fan runs, no spark for ignition.
• Check sequences 10 and 11 (Page 9).
• Check continuity of igniter leads. Replace if shorted or broken.
• Check igniter for carbon buildup, gap spacing (1/8”), secure mounting.
• Replace igniter if porcelain is cracked or if electrodes are rubbery.
Have spark but no flame.
• Check sequences 11, 12 and 13 (Page 9).
• Check for gas pressure on the manifold gauge, if gas is present clean the port holes in burner.
Flame occurs but burner locks out after a few seconds.
• Check the flame rod, if the porcelain is cracked or the electrode is rubbery, replace it.
• If the 1st step checks out, replace the DSI control.
Flame occurs but small.
• Check proper pressure at manifold gauge. If yes:
A) Clean port holes in burner.
B) Check proper position of Gas selector valve (For Natural Gas).
• Not enough pressure at manifold gauge:
A) Check fuel supply.
B) Check liquid strainer for restriction (950HL).
C) Check for restriction at high pressure regulator.
D)Check for restriction at solenoid valves.
Fan does not shut off when thermostat turns off burner.
• Fan should run for 10 to 15 seconds after burner shuts off. Replace DSI control if fan runs over
30 seconds.
Fan runs, no fuel or spark.
• Check to see if the Air Switch light is on, if not, clean or adjust the airflow switch.
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