Lennox mini-split systems are a great way to provide compact, yet powerful 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 risk your mini-split will malfunction. To determine what is malfunctioning, you’ll want to locate where the mini-split error codes are displayed. Understanding what these codes refer to can help ensure fast mini-split repair, especially if professional help is necessary.

What each code means will ultimately depend 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 call the HVAC pros at 1st Choice Heating & Air Conditioning. Our technicians are trained to learn these codes in order to ensure prompt mini-split repair in Mission Viejo. Give us a call at 949-204-0859 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 encounter. To identify what your error code might mean, consider the following:

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

Are there other signs of what malfunctioned? A loud noise coming from an important 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 signifies that communication between the mini-split system’s indoor and outdoor units has been impeded. It could be struggling with intermittent connection problems 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 could stand for a problem with the system’s voltage. A repair technician from 1st Choice Heating & Air Conditioning may refer to it as overcurrent protection. Both very high or low voltage can result in 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 could 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 faulty, the most likely culprit is excessively high temperatures. A high temperature at the discharge line could 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 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 can appear. You may also find the P6 code if the compressor is facing high or low pressure concerns.

Check Your Manual for Your Specific Model

Don’t forget 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 since many of these codes start with electrical problems, professional experience is usually required.

Contact 1st Choice Heating & Air Conditioning for Mini-Split Repair

1st Choice Heating & Air Conditioning 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 diagnose 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 Mission Viejo, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 949-204-0859 today.