Lennox Mini Split Error Codes and What They Might Mean

October 25, 2021

Lennox mini split systems are a great way to provide compact, yet effective temperature control for your home. Some models are built for air conditioning only, while heat pump models can provide both heating and cooling.

But no home comfort system is flawless. There’s always a chance your mini split could malfunction. To identify what is malfunctioning, you should locate where the mini split error codes are displayed. Understanding what these codes refer to can help you kickstart mini split repair, especially if professional help is required.

What the error code means will ultimately depend on the specific model of your mini split system. You can review your manual to find a guide for what each code means. You can also call the HVAC pros at Herman Allen Plumbing, Heating & Cooling. Our technicians are trained to learn these codes in order to provide prompt mini split repair in Greater Richmond. Give us a call at 804-302-6657 to schedule an appointment.

Common Lennox Mini Split Error Codes

While error codes can differ from model to model, there are some codes you’ll be more likely to come across. To determine what your error code might mean, consider the following:

  • Is your model a mini split air conditioner or a mini split heat pump?
  • Are there clear signs of what is happening? A strange noise coming from a key component, for example.

Here are a few of the more common error codes for Lennox mini splits.

E1 – Indoor / Outdoor Unit Communication

In general, an E1 error code signifies that communication between the mini split system’s indoor and outdoor units has been disrupted. It might be facing intermittent connection issues or have failed entirely. When the indoor and outdoor units can’t communicate with one another, it will be unable to properly balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini split heat pump, an E5 error can indicate a problem with the system’s voltage. A repair technician from Herman Allen Plumbing, Heating & Cooling may refer to it as overcurrent protection. Both excessively high or low voltage can create this error code.

For mini split air conditioners, this code may also indicate voltage issues. In other cases, it’s pointing you to a circuit problem with the outdoor temperature sensor.

E6 – Indoor / Outdoor Unit Communication

An E6 error code can also refer to a communication problem between the two units, like an E1 code. It may also be a problem with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will generally be concerned with your mini splits compressor system, housed within the outdoor unit. When the compressor drive is faulty, the most likely culprit is excessively high temperatures. A high temperature at the discharge line can also trigger a P4 code.

P6 – Compressor Switch Open or Drive Board Failure

Your mini split system will have computer boards that ensure the indoor and outdoor units can communicate with one another. If the drive board is damaged, a P6 error code is common.

When temperatures rise above safe levels, a safety switch should protect the electrical components of your mini split system, including any components that control the outdoor compressor. If this switch is open, the P6 code could appear. You may also find the P6 code if the compressor is struggling with high or low pressure issues.

Review the Manual for Your Specific Model

Don’t forget that in general, error codes are specific to each model of a Lennox mini split system. Your manual will have a guide for these error codes and what they should mean. But because many of these codes stem from electrical problems, professional experience is typically required.

Call Herman Allen Plumbing, Heating & Cooling for Mini Split Repair

Herman Allen Plumbing, Heating & Cooling can deliver fast and affordable ductless mini split repair. Whether you own a mini split AC system or a mini split heat pump, our technicians can quickly identify your unique problem.

For some problems, repairs might not be worth it. But that doesn’t mean the mini split replacement process has to be stressful. We can provide equally effective mini split installation in Greater Richmond, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 804-302-6657 today.