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 home comfort system is flawless. There’s always a risk your mini-split could malfunction. To find out what went wrong, you should locate where the mini-split error codes are displayed. Understanding 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 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 Clean Air HVAC. Our technicians are trained to learn these codes in order to ensure prompt mini-split repair in Pacheco. Give us a call at 925-233-6238 to book 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 see. To identify what your error code can mean, consider the following:

Is your model a mini-split air conditioner or a mini-split heat pump?

Are there additional signs of what is happening? A loud noise coming from a specific component, for example.

Here are a few 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 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 may refer to a problem with the system’s voltage. A repair technician from Clean Air HVAC may refer to it as overcurrent protection. Both very high or low voltage can create this error code.

For mini-split air conditioners, this code may 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, similar to an E1 code. It may 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 malfunctioning, 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 could appear. You may also find the P6 code if the compressor is facing high or low pressure issues.

Check the Service Manual for Specifics

Keep in mind 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 since many of these codes start with electrical problems, professional experience is often required.

Trust Clean Air HVAC for Mini-Split Repair

Clean Air HVAC can offer 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 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 Pacheco, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 925-233-6238 today.