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 piece of HVAC equipment is flawless. There’s always a possibility your mini-split can malfunction. To identify what went wrong, you’ll want to locate where the mini-split error codes are displayed. Knowing what these codes refer to can help you kick-start mini-split repair, especially if professional help is needed.

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 contact the HVAC pros at All Solutions Heating & Cooling. Our technicians are trained to recognize these codes in order to deliver prompt mini-split repair in Portland. Give us a call at 971-245-2459 to book an appointment.

What Error Codes for Lennox Mini Splits Are Most Common?

While error codes can differ from model to model, there are some codes you’ll be more likely to see. To determine what your error code could mean, consider 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 indicates that communication between the mini-split system’s indoor and outdoor units has been impeded. It may 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 can stand for a problem with the system’s voltage. A repair technician from All Solutions Heating & Cooling 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 can also represent 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, like an E1 code. It may also be a problem with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will usually be connected to your mini-splits compressor system, found within the outdoor unit. When the compressor drive is faulty, the most likely cause 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