Chapter 6 Troubleshooting
6-2 750-177
Problem Solution
BURNER DOES NOT START 1. No voltage at 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. (Load demand
light will not glow.)
B. Water below required level.
1). Low-water light (and alarm horn) should indicate this condition.
2). Check manual reset button, if provided, on low-water control.
C. Fuel pressure must be within settings of low pressure and high pressure
switches.
4. Fuel valve interlock circuit not completed.
A. Fuel valve auxiliary switch not enclosed.
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 pilot ignition circuit terminal.
2. Spark but no flame.
A. Lack of fuel - no gas pressure, closed valve, empty tank, broken line, etc.
B. Inoperative pilot solenoid.
C. Insufficient or no voltage at pilot ignition circuit terminal.
D.Too much air.
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 switch defective or not properly set.
B. Motor starter interlock contact not closed.
5. Flame detector defective, sight tube obstructed, or lens dirty.
To Next Page
Loading...
Need help?
General
