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 piece of HVAC equipment is flawless. There’s always a possibility your mini split will malfunction. To determine what went wrong, you’ll want to locate where the mini split error codes are displayed. Recognizing what these codes mean can help you kickstart mini split repair, especially if professional help is needed.

What any code means will ultimately rely 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 contact the HVAC pros at 1st Choice Heating & Air Conditioning, Inc.. Our technicians are trained to learn these codes in order to provide prompt mini split repair in Lake Forest. Give us a call at 949-204-0859 to request an appointment.

Common Lennox Mini Split Error Codes

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

  • Is your system a mini split air conditioner or a mini split heat pump?
  • Are there other signs of what is happening? A loud noise coming from a key 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 signifies that communication between the mini split system’s indoor and outdoor units has been hampered. It could be experiencing intermittent connection issues or have failed entirely. When the indoor and outdoor units can’t communicate with one another, it will be unable to effectively 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 1st Choice Heating & Air Conditioning, Inc. may refer to it as overcurrent protection. Both excessively high or low voltage can result in this error code.

For mini split air conditioners, this code could also represent 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 might also be a problem with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will most times be related to your mini splits compressor system, housed 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 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 exceed 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 may 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

Don’t forget 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 should mean. But as many of these codes start with electrical problems, professional experience is typically necessary.

Call 1st Choice Heating & Air Conditioning, Inc. for Mini Split Repair

1st Choice Heating & Air Conditioning, Inc. 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 diagnose your unique problem.

For some problems, repairs may 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 Lake Forest, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 949-204-0859 today.