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 identify 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 needed.

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 Walter's-Eaton's Electric, Plumbing, Heating & AC. Our technicians are trained to learn these codes in order to provide prompt mini-split repair in Ellsworth. Give us a call at 715-318-6728 to book an appointment.

What Error Codes for Lennox Mini Splits Are Most Common?

While error codes may 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 system a mini-split air conditioner or a mini-split heat pump?

Are there clear signs of what malfunctioned? A loud noise coming from an important 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 hampered. It might be facing 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 refer to a problem with the system’s voltage. A repair technician from Walter's-Eaton's Electric, Plumbing, Heating & AC 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 indicate 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, like 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 usually be related to your mini-splits compressor system, found 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 may also lead to a P4 code.

P6 – Compressor Switch Open or Drive Board Failure

Your mini-split system will have computer boards that make sure the indoor and outdoor units can communicate with one another. If the drive board is malfunctioning, 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 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 experiencing high or low pressure issues.

Check Your Manual for Specifics

Remember 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 as many of these codes refer to electrical problems, professional experience is usually necessary.

Call Walter's-Eaton's Electric, Plumbing, Heating & AC for Mini-Split Repair

Walter's-Eaton's Electric, Plumbing, Heating & AC 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 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 Ellsworth, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 715-318-6728 today.