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 deliver both heating and cooling.

But no ductless mini-split is flawless. There’s always a chance your mini-split can malfunction. To determine what happened, you’ll want to locate where the mini-split error codes are displayed. Knowing what these codes mean can help you kick-start mini-split repair, especially if professional help is required.

What the error code means will ultimately depend on the specific model of your mini-split system. You can check 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 ensure prompt mini-split repair in Ballwin and St. Charles. Give us a call at 636-206-4584 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 encounter. To identify what your error code might 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 malfunctioned? A strange noise coming from an important 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 hampered. 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 not be able to adequately 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 unusually high or low voltage can create this error code.

For mini-split air conditioners, this code can also stand for 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, similar to 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 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 culprit is excessively high temperatures. A high temperature at the discharge line may 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 faulty, 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 experiencing high or low pressure concerns.

Check Your 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 offer a guide for these error codes and what they can mean. But since many of these codes refer to electrical problems, professional experience is typically necessary.

Trust 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 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 Ballwin and St. Charles, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 636-206-4584 today.