Source Procedure
Thermostat Disconnect thermostat
wires at the primary control.
•Burner turns off: ther- mostat circuit faulty.
Primary | • Burner not turning off: |
control | primary control faulty. |
Too much heat
Causes
Shorted or welded thermostat contacts
Stuck thermostat bimetal
Thermostat not level
Shorted thermostat wires
Thermostat out of calibration
Thermostat in cold draft
Defective primary control
Too little heat
Correction
Repair or replace the thermostat.
Clear obstruction or replace thermostat. Level thermostat.
Repair short or replace wires.
Replace thermostat.
Correct draft or relocate the thermostat. Replace the defective primary control.
Combus- tion
Check burner combustion for CO2,
stack temperature, and smoke
•Low CO2 less than 10%.
•High smoke reading more than a trace.
Too much combustion air
Air leaks into heat exchanger around inspection door, etc.
Excessive draft
Incorrect burner head adjustment
Dirty or plugged heat exchanger
Insufficient draft
Reduce combustion air.
Correct cause of air leak.
Adjust barometric draft control for correct draft. Correct burner head setting.
Clean heat exchanger.
Readjust burner.
Increase draft.
•High stack tempera- ture is more than 550F net.
Oil Pres- | Inspect fire and check |
sure | oil pressure. |
Incorrect burner head adjustment
Too little combustion air
Too little blower air
Dirty or plugged heat exchanger Dirty blower wheel
Dirty furnace air filters
Restricted or closed registers/dampers Partially plugged or defective nozzle Oil pressure too low: less than 100 psi.
Correct burner setting.
Increase combustion air.
Check for high static pressure.
Check HEAT selector pin per wiring diagram (figure 18, page 16).
Clean heat exchanger.
Clean blower wheel.
Clean or replace filter.
Readjust registers or dampers.
Replace nozzle.
Increase oil pressure top 100psi.
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O23V SERIES
