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

But no home comfort system is flawless. There’s always a possibility your mini-split could malfunction. To identify what went wrong, you’ll want to 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 any code means will ultimately depend 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 call the HVAC pros at Precision Mechanical. Our technicians are trained to learn these codes in order to ensure prompt mini-split repair in Rapid City. Give us a call at 605-206-3766 to request an appointment.

Common Error Codes for Lennox Mini Splits

While error codes can differ from model to model, there are some codes you’ll be more likely to come across. To determine what your error code might mean, ask yourself the following:

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

Are there other signs of what is happening? A loud 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 signifies that communication between the mini-split system’s indoor and outdoor units has been disrupted. It could be facing intermittent connection problems or have failed entirely. When the indoor and outdoor units can’t communicate with one another, it will be unable 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 Precision Mechanical 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 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, similar to an E1 code. It might also be a problem with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will most times be connected to your mini-splits compressor system, found 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 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 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 have a guide for these error codes and what they can mean. But because many of these codes refer to electrical problems, professional experience is often necessary.

Call Precision Mechanical for Mini-Split Repair

Precision Mechanical 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 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 Rapid City, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 605-206-3766 today.