11
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 fan switch & thermostat are ON.
• Check sequences 1 through 4 (Page 4)
Fan runs, no spark for ignition.
• Check sequences 5, 10 and 11 (Page 4-5)
• 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 14 (Page 5)
• Check for gas pressure on the manifold gauge, if gas is present clean the port holes in the burner
Flame occurs but burner locks out after a few seconds.
• Check sequence 1 (Page 4)
• Check for proper polarity of incoming voltage
A) Place one lead of voltmeter on ground and the other lead on the 20 amp fuse
B) Place one lead of voltmeter on ground and the other lead on the neutral or white wire from
power cord. Reading should be “0” volts.
• Check the igniter sensor electrodes, if the porcelain is cracked or the electrodes are rubbery
replace them
• If the 1st 4 steps check, replace the ignition 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
A) Check fuel supply
B) Check liquid strainer for restriction (1800L)
C) Check for restriction at Hi pressure regulator
D)Check for restriction at solenoid valve
Fan does not shut off when thermostat turns off burner.
• Check for proper wiring on fan delay timer
• Fan should run for 5 to 7 seconds after burner shuts off. Replace fan delay timer if fan runs over
10 seconds.
Summary of Contents for 1800
Page 16: ...16 Note New Fenwal Control Board ...
Page 18: ...18 ...
