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 powerful 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 ductless mini split is flawless. There’s always a chance your mini split can malfunction. To determine what is malfunctioning, you’ll want to locate where the mini split error codes are displayed. Knowing what these codes mean can help you kickstart mini split repair, especially if professional help is required.

What any code means will ultimately depend on the specific model of your mini split system. You can consult your manual to find a guide for what each code means. You can also call the HVAC pros at Stanford Heating & Cooling. Our technicians are trained to learn these codes in order to deliver prompt mini split repair in Bloomfield. Give us a call at 812-825-8695 to request 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 see. To identify what your error code may mean, ask yourself 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 loud noise coming from a specific component, for example.

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

E1 – Indoor / Outdoor Unit Communication

In general, an E1 error code means that communication between the mini split system’s indoor and outdoor units has been impeded. It could be experiencing intermittent connection problems 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 could indicate a problem with the system’s voltage. A repair technician from Stanford Heating & Cooling may refer to it as overcurrent protection. Both unusually high or low voltage can result in 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 an issue with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will generally be related to your mini splits compressor system, located within the outdoor unit. When the compressor drive is not working, the most likely cause is excessively high temperatures. A high temperature at the discharge line may also lead to 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 will protect the electrical components of your mini split system, including any components that manage the outdoor compressor. If this switch is open, the P6 code can appear. You may also find the P6 code if the compressor is facing high or low pressure concerns.

Review the Manual for Your Specific Model

Remember that in general, error codes are different for each model of a Lennox mini split system. Your manual will provide a guide for these error codes and what they can mean. But because many of these codes start with electrical problems, professional experience is typically necessary.

Call Stanford Heating & Cooling for Mini Split Repair

Stanford Heating & Cooling can provide 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 diagnose 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 Bloomfield, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 812-825-8695 today.