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 home comfort system is flawless. There’s always a chance your mini-split can malfunction. To identify what happened, you should locate where the mini-split error codes are displayed. Understanding what these codes refer to can help you kick-start 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 review your manual for a guide for what each code means. You can also trust the HVAC pros at Three Rivers Heating & Cooling. Our technicians are trained to learn these codes in order to deliver prompt mini-split repair in Portland. Give us a call at 503-213-4433 to request 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 encounter. To determine what your error code can 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 key 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 disrupted. It might be facing intermittent connection problems 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 may refer to a problem with the system’s voltage. A repair technician from Three Rivers 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 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 related to your mini-splits compressor system, found within the outdoor unit. When the compressor drive is not working, the most likely reason 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 make sure the indoor and outdoor units can communicate with one another. If the drive board is damaged, 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 may appear. You may also find the P6 code if the compressor is facing high or low pressure issues.

Check the 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 because many of these codes refer to electrical problems, professional experience is often necessary.

Trust Three Rivers Heating & Cooling for Mini-Split Repair

Three Rivers Heating & Cooling 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 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 Portland, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 503-213-4433 today.