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

What each code means will ultimately rely on the specific model of your mini split system. You can consult your manual for a guide for what each code means. You can also contact the HVAC pros at Air Alliance Team. Our technicians are trained to recognize these codes in order to deliver prompt mini split repair in Ballwin and St. Charles. Give us a call at 636-206-4250 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 come across. To learn what your error code may mean, ask yourself 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 strange 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 indicates that communication between the mini split system’s indoor and outdoor units has been impeded. 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 effectively balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini split heat pump, an E5 error may stand for a problem with the system’s voltage. A repair technician from Air Alliance Team 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 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, like an E1 code. It might 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, 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 faulty, 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 can appear. You may also find the P6 code if the compressor is struggling with high or low pressure issues.

Check 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 stem from electrical problems, professional experience is usually necessary.

Call Air Alliance Team for Mini Split Repair

Air Alliance Team 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 Ballwin and St. Charles, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 636-206-4250 today.