Nordyne O4MD Installation, Operation And Maintenance Manual page 27

Problem Possible Cause
Fuel oil leak.
Stack temperature too
Excessive fuel oil high.
consumption.
...continued
Thermostat improperly
adjusted or in poor
location.
Remedy
Check fuel oil line for leaks. Repair or replace if
necessary.
Check stack temperature. Stack temperatures will
normally range from 350 ° to 450°F. Check draft
regulator. Draft should be set to 0.02 in. w.c.
Check thermostat heat anticipator setting against
measured amperage draw. Increase heat anticipator
setting if necessary. If the thermostat is being
influenced by drafts, sunlight, duct work, etc., relocate
to more suitable location.
Insufficient combustion
air adjustment at oil Adjust the oil burner combustion air shutter and draft
burner, or improper draft regulator to gain the highest CO2 possible with a
Too much smoke. Bacharach trace smoke.
pressure.
Heat exchanger partially Check for soot build-up in heat exchanger flue
clogged, passages, especially in the outer radiator.
Poor alignment between Check alignment, blast tube should be centered with
oil burner blast tube and fire pot burner opening. Oil burner head should be 1/4
fire pot. inch back from the inside surface of the fire pot.
Flame impingement Check nozzle size and angle. (See Appendix A). Check
Soot building up on caused by Incorrect
distance from head to inside surface of the fire pot.
air tube (end coning), nozzle angle.
Incorrect electrode
Check the electrode settings and "Z" dimension.
settings.
Defective fire-pot Check fire-pot. Repair or replace.
Air flow blocked or dirty Clean or replace air filter.
air filter.
Thermostat adjustments
or location.
Insufficient air flow.
Check thermostat heat anticipator setting against
measured amperage draw. Increase heat anticipator
setting if necessary. If the thermostat is being
influenced by drafts, sunlight, duct work, etc., relocate
to more suitable location.
Check all dampers. Open closed dampers including
registers in unused rooms. Check system temperature
rise. If temperature rise is too high, speed up blower
fan.
Furnace will not
warm home to Test high limit function of all limit switches. Use a duct
desired temperature Defective high limit thermometer to assess accuracy of limit control. Check
control, for obstructions to airflow around limit switch bi-metal
elements. Replace control if necessary.
Check nozzle. If problem is not caused by air flow
Under-sized nozzle.
problems, use larger nozzle, if permitted by rating plate.
Blower fan motor Check blower fan motor amperage draw. Check motor
stopping intermittently on ventilation ports, clean if necessary. Replace motor if
overload, necessary.
Burner motor stopping Check burner motor. Replace if necessary.
intermittently on overload.
Home does not heat Improper distribution of This is not likely to be a furnace problem. Balance duct
evenly heat. system.
2"7 153B0801