Lennox Mini Split Error Codes and What They Could Mean

October 25, 2021

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

But no ductless mini split is flawless. There’s always a risk your mini split could malfunction. To identify what went wrong, you’ll want to locate where the mini split error codes are displayed. Recognizing what these codes refer to can help ensure fast mini split repair, especially if professional help is needed.

What the error code means will ultimately rely on the specific model of your mini split system. You can check your manual to find a guide for what each code means. You can also trust the HVAC pros at Custom Air Systems Inc. Our technicians are trained to recognize these codes in order to ensure prompt mini split repair in Port St. Lucie. Give us a call at 772-247-2283 to request an appointment.

Common Lennox Mini Split Error Codes

While error codes will differ from model to model, there are some codes you’ll be more likely to encounter. To determine what your error code can 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 some 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 disrupted. It may 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 properly balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini split heat pump, an E5 error could refer to a problem with the system’s voltage. A repair technician from Custom Air Systems Inc 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 represent voltage issues. In other cases, it’s alerting 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 usually be concerned with your mini splits compressor system, housed within the outdoor unit. When the compressor drive is malfunctioning, the most likely cause is excessively high temperatures. A high temperature at the discharge line could also result in 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 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 may appear. You may also find the P6 code if the compressor is facing 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 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 usually required.

Call Custom Air Systems Inc for Mini Split Repair

Custom Air Systems Inc 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 specific 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 Port St. Lucie, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 772-247-2283 today.