CleaverBrooks profire q, Installation, Operation And Maintanance

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750-370
ProFire Q Series Manual 6-3
Troubleshooting
6.3 — Problem/Possible Causes
Problem Possible Causes
Burner Does Not Start 1. No voltage at the program relay power input terminals.
a. Main disconnect switch open.
b. Blown control circuit fuse.
c. Loose or broken electrical connection.
2. Program relay safety switch requires resetting.
3. Limit circuit not completed - no voltage at end of limit circuit program relay terminal.
a. Pressure or temperature is above setting of operation control
b. Water below required level. Low-water light (and alarm horn) should indicate this
condition. Check manual reset button, if provided, on low-water control.
c. Fuel pressure must be within settings of low pressure and high pressure switches.
d. Check burner air proving switch and high-fire limit switch.
4. Fuel valve interlock circuit not completed.
a. Fuel valve auxiliary switch not closed.
No Ignition 1. Lack of spark.
a. Electrode grounded or porcelain cracked.
b. Improper electrode setting.
c. Loose terminal on ignition cable, cable shorted.
d. Inoperative ignition transformer.
e. Insufficient or no voltage at ignition circuit terminal.
2. Spark but no flame.
a. Lack of fuel - no gas pressure, closed valve, empty tank, broken line, etc.
3. Low-fire switch open in low-fire proving circuit.
a. Damper motor not closed, slipped cam, defective switch.
b. Damper jammed or linkage binding.
4. Running interlock circuit not completed.
a. Combustion air proving switches defective or not properly set.
b. Motor starter interlock contact not closed.
Problem Possible Causes
No Main Flame 1. Insufficient ignition flame.
2. Gas fired unit:
a. Manual gas cock closed.
b. Main gas valve inoperative.
c. Gas pressure regulator inoperative.
3. Flame detector defective, sight tube obstructed or lens dirty.
4. Insufficient or no voltage at main fuel valve circuit terminal.