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 provide both heating and cooling.

But no piece of HVAC equipment is flawless. There’s always a possibility your mini-split can malfunction. To determine what went wrong, 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 needed.

What each code means will ultimately rely on the specific model of your mini-split system. You can consult your manual to find a guide for what each code means. You can also contact the HVAC pros at Precision Mechanical. Our technicians are trained to learn these codes in order to provide prompt mini-split repair in Rapid City. Give us a call at 605-206-3766 to request an appointment.

Common Lennox Mini-Split Error Codes

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

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

Are there additional signs of what is happening? A loud 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 means that communication between the mini-split system’s indoor and outdoor units has been hampered. It might be struggling with 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 properly balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini-split heat pump, an E5 error can indicate 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 produce this error code.

For mini-split air conditioners, this code could also indicate 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, similar to 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 malfunctioning, the most likely cause is excessively high temperatures. A high temperature at the discharge line can also lead to 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 manage 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.

Consult the Manual for Your Specific Model

Keep in mind 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 stem from electrical problems, professional experience is often necessary.

Call Precision Mechanical for Mini-Split Repair

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

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