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 piece of HVAC equipment is flawless. There’s always a possibility your mini-split could malfunction. To identify what is malfunctioning, you should locate where the mini-split error codes are displayed. Knowing what these codes mean can help ensure fast mini-split repair, especially if professional help is necessary.

What the error code means will ultimately depend on the specific model of your mini-split system. You can review your manual for a guide for what each code means. You can also trust the HVAC pros at ACS Heating and Air Conditioning. Our technicians are trained to learn these codes in order to provide prompt mini-split repair in Tucker. Give us a call at 770-450-1539 to request an appointment.

Common Error Codes for Lennox Mini Splits

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

Is your system a mini-split air conditioner or a mini-split heat pump?

Are there additional 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 indicates that communication between the mini-split system’s indoor and outdoor units has been impeded. It might 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 adequately balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini-split heat pump, an E5 error may indicate a problem with the system’s voltage. A repair technician from ACS Heating and Air Conditioning may refer to it as overcurrent protection. Both excessively high or low voltage can produce this error code.

For mini-split air conditioners, this code can also stand for 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, similar to 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 usually be related to your mini-splits compressor system, housed within the outdoor unit. When the compressor drive is malfunctioning, the most likely culprit is excessively high temperatures. A high temperature at the discharge line could also trigger a P4 code.

P6 – Compressor Switch Open or Drive Board Failure

Your mini-split system will have computer boards that make sure the indoor and outdoor units can communicate with one another. If the drive board is malfunctioning, 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 control the outdoor compressor. If this switch is open, the P6 code can appear. You may also find the P6 code if the compressor is struggling with high or low pressure concerns.

Review Your Manual for Your Specific Model

Keep in mind that in general, error codes are specific to each model of a Lennox mini-split system. Your manual will provide a guide for these error codes and what they can mean. But as many of these codes start with electrical problems, professional experience is usually required.

Call ACS Heating and Air Conditioning for Mini-Split Repair

ACS Heating and Air Conditioning 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 Tucker, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 770-450-1539 today.