Nordyne Furnace Troubleshooting

Nordyne O4MD Furnace Troubleshooting

ProblemPossible CauseRemedy
Furnace will not start.Thermostat not calling for heat.Check thermostat and adjust. Also, check thermostat for accuracy; if it is a mercury switch type, it might be off level.
No power to furnace.Check furnace switch, main electrical panel furnace fuse or circuit breaker. Also look for any other hand operated switch, such as an old poorly located furnace switch that was not removed during furnace replacement.
Thermostat faulty.Check reset button on protector relay. Remove thermostat wires from protector relay terminals T1-T2. Place a jumper across T1-T2. If furnace starts, replace thermostat, thermostat sub-base (if equipped), or both.
Protector relay faulty.Check reset button on protector relay. Remove thermostat wires from protector relay terminals T1-T2. Check for 24v across T1-T2. If no voltage is present, check for 115v to protector relay. If 115v is present, replace protector relay.
Photo Cell wiring shorted or room light leaking into photo cell compartmentCheck cad cell wiring for short circuits. Also, check for room light leaking into cad cell compartment. Repair light leak if necessary.
Open safety switch.Check for open limit or auxiliary limit, open door switch (if equipped). Also, check internal wiring connections; loose connectors, etc.
Furnace will not start without first pushing protector relay reset button. (Happens on frequent basis)No fuel oil.Check fuel oil supply. Check that all hand operated fuel oil valves are in the open position. Fill oil storage tank if necessary.
Clogged nozzle.Replace nozzle with high quality replacement. Use rating plate or Tables in Appendix A as a guide.
Clogged oil filter.Replace oil tank filter or in-line filter if used.
Low oil pump pressure.Connect pressure gauge to oil pump. Adjust pump pressure, or replace oil pump if necessary. Ensure that erratic pressure readings are not caused by defective fuel oil line.
Air getting into fuel oil lines, or fuel oil line dirty, clogged, or in some manner defective.Check fuel oil lines. Replace any compression fittings found with high quality flared fittings. Check for any signs of oil leaks. Any oil leak is a potential source of air or contaminants.
Defective burner motor.Check burner motor. If burner motor is cutting out on over-load, determine why. Replace if necessary.
Furnace starts, but cuts out requiring manually resetting the oil protector reset button.Photo Cell (Cad Cell) defective.If cad cell is dirty, clean it. (Determine why cad cell is getting dirty). If cad cell is poorly aimed, realign it. NOTE: The cad cell should have a resistance of 100K £2 in absence of light; a maximum of 1500 LI in the presence of light. Ensure that room light is not leaking into the cad cell compartment.
Oil burner sputtering at nozzleElectrodes out of adjustment or defective.Check electrode settings. Check electrodes for dirt build-up or cracks in porcelain.
Poor transformer high voltage connections or defective transformer.Check contacts between transformer and electrodes. If OK, replace transformer.
Fuel oil filter clogged.Replace fuel oil storage tank filter and / or fuel oil in-line filter.
Defective oil pump.Check burner motor / fuel oil pump coupling. Check oil pump pressure. Replace fuel oil pump if necessary.
Fuel oil line partially clogged or contains air.Bleed air from oil line. If problem persists, replace oil line.
Excessive fuel oil consumption.System temperature rise too high.System temperature rise should not exceed 85°F. Check for clogged air filters. Check blower fan for excess dirt build-up or debris. Speed up blower fan if necessary.
Blower fan control out of adjustment, (fan stops too soon).Check fan control settings. The fan control is adjusted with a duct thermometer in the supply air plenum take- off or first few inches of the supply air trunk duct. The " fan off" setting should be 90° - 100°F. Once set. the "fan on" setting is normally adjusted 25° - 30°F higher than the "fan off' setting.

Nordyne M1B Furnace Troubleshooting

ProblemPossible CauseRemedy
Excessive fuel oil consumption.Fuel oil leak.Check fuel oil line for leaks. Repair or replace if necessary.
Stack temperature too high.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.
Thermostat improperly adjusted or in poor location.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.
Too much smoke.Insufficient combustion air adjustment at oil burner, or improper draft pressure.Adjust the oil burner combustion air shutter and draft regulator to gain the highest C0 2 possible with a Bacharach trace smoke.
Heat exchanger partially clogged.Check for soot build-up in heat exchanger flue passages, especially in the outer radiator.
Poor alignment between oil burner blast tube and fire pot.Check alignment, blast tube should be centered with fire pot burner opening. Oil burner head should be V* inch back from the inside surface of the fire pot.
Soot building up on air tube (end coning).Flame impingement caused by Incorrect nozzle angle.Check nozzle size and angle. Check distance from head to inside surface of the fire pot.
Incorrect electrode settings.Check the electrode settings and “Z" dimension.
Defective fire-potCheck fire-pot. Repair or replace.
Air flow blocked or dirty air filter.Clean or replace air filter.
Thermostat adjustments or location.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.
Furnace will notInsufficient air flow.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.
warm home to desired temperatureDefective high limit control.Test high limit function of all limit switches. Use a duct thermometer to assess accuracy of limit control. Check for obstructions to airflow around limit switch bi-metal elements. Replace control if necessary.
Under-sized nozzle.Check nozzle. If problem is not caused by air flow problems, use larger nozzle, if permitted by rating plate.
Blower fan motor stopping intermittently on overload.Check blower fan motor amperage draw. Check motor ventilation ports, clean if necessary. Replace motor if necessary.
Burner motor stopping intermittently on overload.Check burner motor. Replace if necessary.
Home does not heatImproper distribution ofThis is not likely to be a furnace problem. Balance duct
Supply air temperature too hot.Airflow blocked or dirty air filter.Clean or replace air filter.
Insufficient airflow.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.
Supply air temperature too cool.Excess airflow.Check system temperature rise. Slow down blower fan if necessary.
Excessive duct losses.Check supply air ductwork. Seal leaky joints and seams. Insulate ductwork if necessary.
Supply air temperature too cool during first moments of furnace cycle.Fan control "fan on" setting too low.No adjustments available for L4064W fan / limit control). Register air deflectors may help.
Excessive duct losses.Check supply air ductwork. Seal leaky joints and seams. Insulate ductwork if necessary.

Nordyne TA UPFLOW Furnace Troubleshooting

Green LEDRed LEDDiagnostic Description
OffOffControl Fault (No Power)
FlashFlashL1/Neutral Polarity Fault
OnOnNormal Operation
OnFlashPressure Switch Closed Fault
FlashOnPressure Switch Open Fault
FlashOffOpen Limit Switch Fault
OnOffMotor Fault

Nordyne 045C-23ASA Furnace Troubleshooting

Green LEDRed LEDDiagnostic Description
OffOffControl Fault (No Power)
OnOnNormal Operation
OnFlashMotor Fault
FlashOnTwin Fault (no motor fault)
FlashFlashCommunications Fault
OffOffControl Fault (No Power)
OnOnNormal Operation
OnFlashMotor Fault
FlashFlashCommunications Fault