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 piece of HVAC equipment is flawless. There’s always a chance your mini-split can malfunction. To determine what went wrong, you’ll want to locate where the mini-split error codes are displayed. Understanding what these codes mean can help ensure fast mini-split repair, especially if professional help is required.

What the error 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 ACS Heating and Air Conditioning. Our technicians are trained to recognize these codes in order to deliver prompt mini-split repair in Tucker. Give us a call at 770-450-1539 to schedule an appointment.

Common Lennox Mini-Split Error Codes

While error codes can differ from model to model, there are some codes you’ll be more likely to come across. To learn 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 additional signs of what is happening? A strange 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 could be struggling with intermittent connection issues or have failed entirely. When the indoor and outdoor units can’t communicate with one another, it will not be able to effectively balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini-split heat pump, an E5 error could 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 unusually high or low voltage can result in this error code.

For mini-split air conditioners, this code may 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, located within the outdoor unit. When the compressor drive is malfunctioning, the most likely reason 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 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 could appear. You may also find the P6 code if the compressor is struggling with high or low pressure issues.

Review Your Service Manual for the Exact Model

Keep in mind that in general, error codes are different for each model of a Lennox mini-split system. Your manual will have a guide for these error codes and what they should mean. But as many of these codes refer to electrical problems, professional experience is often necessary.

Call ACS Heating and Air Conditioning for Mini-Split Repair

ACS Heating and Air Conditioning 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 Tucker, bringing your new system online with little to no comfort disruption.

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