SourceProcedure
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.
Causes | Correction |
| |
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. |
|
Source
Poor Fire
Flame Detector
Procedure
After burner fires,
immediately jumper across flame detector terminals at
the primary control.
•If burner continues to run, this may be due to poor fire. Inspect fire.
•If fire is good, fault is in the flame detector.
Check detector circuit.
Causes
Unbalanced fire
Too much air -
Too little air - - long dirty fire
Excessive draft
Too little draft or restriction
Dirty cad cell face
Faulty cad cell - exceeds 15000 hms Loose or defective cad cell wires
Correction
Replace nozzle
Reduce combustion air - check combustion.
Increase combustion air - check combustion.
Adjust barometric damper for correct draft.
Correct draft or remove restriction.
Clean cad cell face.
Replace cad cell.
Secure connections or replace cad cell holder and wire leads.
Primary Control olf burner locks out on
safety, fault is in the pri- mary control.
SourceProcedure
Thermostat Check thermostat.
Limit Control Connect voltmeter between line voltage connections to primary control (black & white leads). If burner cycles due to power interruption, it is cycling on limit.
Primary control circuit defective
Causes
Heat anticipator set too low
Vibration at thermostat
Thermostat in the path of a warm air draft
Dirty furnace air filters
Blower running too slow
Blower motor seized or burned out
Blower bearings seized
Blower wheel dirty
Blower wheel in backward
Wrong motor rotation
Restrictions in return or supply air system
Adjustable limit control set too low
Replace primary control.
Correction
Correct heat anticipator setting.
Correct source of vibration.
Shield thermostat from draft or relocate.
Clean or replace filter.
Increase blower speed to maintain proper temp. rise.
Check for high static pressure.
Check HEAT selector pin per wiring diagram (figure 18, page 16).
Replace motor.
Replace bearings and shaft.
Clean blower wheel.
Reverse blower wheel.
Replace with properly rotating wheel.
Correct cause of restriction.
Reset limit to maximum stop setting.
table continued on next page
Page 21
O23V SERIES
