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Nordyne Heat Pump Troubleshooting - PartsAPS

nordyne heat pump troubleshooting

Are you looking for Nordyne heat pump troubleshooting? Here, you can find a guide on Nordyne heat pump problems and possible causes. Since problems with the system often lead to interruptions or malfunctions, you need to fix them immediately. In this post, you can check the flash codes and their descriptions with your Nordyne heat pump.

Nordyne Heat Pump Troubleshooting Guide

When an abnormal system condition occurs, the comfort alert module displays the appropriate ALERT, and/ or TRIP LED will flash a number of times consecutively, pause and then repeat the process. To identify the flash code number, you need to count the number of consecutive flashes. Every time the comfort ALERT module powers up, the last alert flash code that occurred prior to shutdown will be displayed for one minute.

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Green “Power”

If the status of LED shows as green power, it describes that the module has power. The supply voltage is present at module terminals.

Red "TRIP”

It indicates that the thermostat demand signal Y is present but the compressor is not running. To erase this status, you need to check the following.

  • The compressor protector is open.
  • Outdoor unit’s power disconnect is open.
  • The compressor circuit breaker or fuse is open.
  • Broken wire is not providing contact.
  • Open the low-pressure switch if it is present in the system and the compressor contactor has failed to open.

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Yellow “ALERT" Flash Code 1

Means that the long run time compressor is running long run cycles. For this, you have to do the following troubleshooting steps.

  • It may because of the low refrigerant charge. So, charge it.
  • The evaporator blower might not be running.
    • Check blower relay coil and contacts.
    • Inspect blower motor capacitor.
    • Examine the blower motor for failure or blockage.
    • Check evaporator blower wiring and connectors.
    • Verify the indoor blower control board.
    • Check thermostat wiring for open circuit.
  • The evaporator coil is frozen.
    • Check for low suction pressure.
    • You have to check for excessively low thermostat settings.
    • Check evaporator airflow (coil blockages or return air filter).
    • Also, verify ductwork or registers for blockage.
  • Faulty metering device. Check if TXV or fixed orifice is stuck/ closed or defective.
  • The condenser coil is dirty.
  • Defective thermostat. You need to check the thermostat sub-base or wiring for a short circuit.
  • Comfort alert failure.

Yellow “ALERT” Flash Code 2

Heat pump pressure trip

There may be high head pressure in the system.

  • Check the high-pressure switch if it is present in the unit.
  • Verify the unit if it is overcharged with refrigerant.
  • Check for non-condensable in your heat pump.

Discharge or suction

The air circulation might be poor, i.e., it may get dirty, blocked, or damaged.

Pressure out of limits

It may because of condenser fan is not running. So, you will have to verify the following:

  • Fan capacitor.
  • Fan wiring and connectors.
  • Condenser fan motor for blockage or failure.

Compressor is overloaded

  • The return air duct has substantial leakage.
  • If the low-pressure switch is present in the system, make sure to refer to the flash code 1 troubleshooting information.

Yellow “ALERT” Flash Code 3

This LED status indicates that there may be short cycling or the compressor is running briefly. Check the following:

  • The thermostat demand signal is intermittent.
  • Low line voltage. Check the power source if the voltage at disconnect is low.
  • Excessive liquid refrigerant in the compressor.
  • Compressor bearings are seized.

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Yellow "ALERT" Flash Code 4

When there is a locked rotor, you can notice flash code 4 status.

  • See if the run capacitor has failed.
  • Check for low line voltage.
  • Verify the wiring connections
  • Check for excessive liquid refrigerant in the compressor.
  • Measure the compressor oil level.

Yellow “ALERT” Flash Code 5

It describes the open circuit in the system. If you are observing this status, check the below things:

  • System's outdoor unit power disconnect is open.
  • Problem with the circuit breaker or fuse.
  • Compressor contactor has failed to open. So, you need to check
    • Compressor contactor wiring and connectors.
    • Contactor failure such as burned, pitted, or open.
    • Wiring & connectors between supply and compressor.
    • The low pilot voltage at compressor contactor coil.
    • A high-pressure switch is open and requires manual reset.
  • Open circuit in the compressor supply wiring or connections.
  • Compressor windings might be damaged. So, you have to check the compressor motor winding resistance.

Yellow “ALERT” Flash Code 6

Open start circuit current only in the run circuit. To fix this issue, try the following steps.

  • The run capacitor may be failed. Verify it. You have to replace it if necessary.
  • Open circuit in compressor start wiring or connections. So, check the wiring as well as connectors between the compressor S terminal and power supply.
  • Compressor start winding could be damaged. Inspect compressor motor winding resistance.

Yellow “ALERT” Flash Code 7

It indicates the open run circuit current only in the start circuit.

  • It may because of an open circuit in compressor run wiring or connections. Check wiring & connections between supply and compressor R terminal.
  • Check if the compressor run winding is damaged.

Yellow “ALERT” Flash Code 8

This flash code notifies you that welded contactor compressor is running always. Know the causes of this problem below.

  • The compressor contactor has failed to close.
  • Thermostat demand signal is not connected to the module.

Yellow “ALERT” Flash Code 9

If there is a low voltage control circuit < 17 VAC, you will get this status.

  • There may be an overloaded control circuit transformer.
  • Because of low line voltage.
  • You need to check the wiring connections.

Here, we have updated the instructions for Nordyne R-410A troubleshooting. However, you can get your specific model instructions in the manufacturer’s manual. You can follow them to fix basic issues.

Final Words

Nordyne heat pumps provide many years of safe and dependable comfort if you install and maintain them properly. With regular maintenance, your unit will operate satisfactory year after year. Abuse, improper maintenance, or use can shorten the life of the heat pump and get problems. To achieve optimum performance and minimize equipment failure, it is recommended that perform periodic maintenance. We hope this Nordyne heat pump troubleshooting guide helped you to fix the issues.

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