Lennox International Inc. o23v - Manual (Page 28)

Page 28
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.
Electrodes electrodes and leads.
Dirty electrodes and leads
Eroded electrode tips Clean electrode tips and reset the
gap and correct position tips See
Improper electrode gap spacing
gap and correct position tips. See
figure 15.
Improper position of electrode tips
figure 15.
Damaged Transformer Leads Replace Transformer
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.
to transformer primary.
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 Low line voltage Check voltage at power source.
Correct cause of voltage drop or
the call power company.
hand to check for binding or
excessive drag.
Pump or blower overloading motor Correct cause of overloading.
excessive drag.
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 Unbalanced fire Replace nozzle
immediately jumper across
flame detector terminals at
the primary control.
Too much air − −lean short fire Reduce combustion air − check
combustion.
the primary control.
S
If burner continues to
run, this may be due to
Too little air − − long dirty fire Increase combustion air − check
combustion.
run, this may be due to
poor fire. Inspect fire.
Excessive draft Adjust barometric damper for correct draft. p p
Too little draft or restriction Correct draft or remove restriction.
Flame Detector
S
If fire is good, fault is in Dirty cad cell face Clean cad cell face. g ,
the flame detector.
Check detector circuit
Faulty cad cell − exceeds 15000 hms Replace cad cell.
Check detector circuit.
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.