Lennox mini-split systems are a solid way to provide compact, yet effective 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 ductless mini-split is flawless. There’s always a risk your mini-split will malfunction. To identify what is malfunctioning, you should locate where the mini-split error codes are displayed. Recognizing what these codes mean can help you kick-start mini-split repair, especially if professional help is necessary.

What any code means will ultimately depend on the specific model of your mini-split system. You can check your manual for a guide for what each code means. You can also call the HVAC pros at Ilten's. Our technicians are trained to learn these codes in order to deliver prompt mini-split repair in Cedar Rapids. Give us a call at 319-208-2351 to schedule an appointment.

What Error Codes for Lennox Mini Splits Are Most Common?

While error codes will differ from model to model, there are some codes you’ll be more likely to see. To learn what your error code could mean, ask yourself the following:

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

Are there clear 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 signifies that communication between the mini-split system’s indoor and outdoor units has been disrupted. It might be experiencing 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 adequately balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini-split heat pump, an E5 error can refer to a problem with the system’s voltage. A repair technician from Ilten's may refer to it as overcurrent protection. Both excessively high or low voltage can produce 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, like an E1 code. It could also be a problem with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will generally 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 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 faulty, 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 the Service Manual for the Exact Model

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

Contact Ilten's for Mini-Split Repair

Ilten's 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 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 Cedar Rapids, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 319-208-2351 today.