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Troubleshooting: Burner starts, but no flame is established
Source
Correction
Causes
Procedure
Ignition
Electrodes
Remove gun assembly and inspect
electrodes and leads.
Fouled or shorted electrodes
Clean electrode leads.
Dirty electrodes and leads
Eroded electrode tips
Clean electrode tips and reset the
gap to 5/32 inches and correctly
position tips.
Improper electrode gap spacing
Improper position of electrode tips
Bad buss bar connection
Re−tension and realign.
Cracked or chipped insulators
Replace electrode.
Cracked or burned lead insulators
Replace electrode leads.
Ignition
Transformer
Connect ignition leads to the
transformer. Start burner and
observe spark. Check line voltage
to transformer primary.
Low line voltage
Check voltage at power source.
Correct cause of voltage drop or call
the power company.
Burned out transformer windings.
Replace the transformer.
No spark or weak spark
Properly ground the transformer
case.
Burner Motor
Motor does not come up to speed
and trips out on overload. Turn off
power and rotate blower wheel by
hand to check for binding or
excessive drag.
Low line voltage
Check voltage at power source.
Correct cause of voltage drop or the
call power company.
Pump or blower overloading motor
Correct cause of overloading.
Faulty motor
Replace motor.
Troubleshooting: Burner starts and fires, but lock out on safety
Source
Procedure
Causes
Correction
Poor Fire
After burner fires,
immediately jumper across
flame detector terminals at
the primary control.
S
If burner continues to
run, this may be due to
poor fire. Inspect fire.
Unbalanced fire
Replace nozzle
Too much air − −lean short fire
Reduce combustion air − check
combustion.
Too little air − − long dirty fire
Increase combustion air − check
combustion.
Excessive draft
Adjust barometric damper for correct draft.
Too little draft or restriction
Correct draft or remove restriction.
Flame Detector
S
If fire is good, fault is in
the flame detector.
Check detector circuit.
Dirty cad cell face
Clean cad cell face.
Faulty cad cell − exceeds 15000 hms
Replace cad cell.
Loose or defective cad cell wires
Secure connections or replace cad cell
holder and wire leads.
Primary Control
S
If burner locks out on
safety, fault is in the pri-
mary control.
Primary control circuit defective
Replace primary control.
Troubleshooting: Burner starts and fires, but short cycles (too little heat)
Source
Procedure
Causes
Correction
Thermostat
Check thermostat.
Heat anticipator set too low
Correct heat anticipator setting.
Vibration at thermostat
Correct source of vibration.
Thermostat in the path of a warm air
draft
Shield thermostat from draft or relocate.
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