Lennox Mini Split Error Codes and What They Could Mean

October 25, 2021

Lennox mini split systems are a solid 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 possibility your mini split will malfunction. To identify what is malfunctioning, you should locate where the mini split error codes are displayed. Understanding what these codes refer to can help you kickstart 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 for a guide for what each code means. You can also call the HVAC pros at Marcos AC & Heating. Our technicians are trained to recognize these codes in order to ensure prompt mini split repair in Houston. Give us a call at 713-469-3357 to schedule an appointment.

Common Lennox Mini Split Error Codes

While error codes may differ from model to model, there are some codes you’ll be more likely to come across. To identify 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 other signs of what malfunctioned? A loud noise coming from a key component, for example.

Here are a few 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 hampered. It may be experiencing intermittent connection issues or have failed entirely. When the indoor and outdoor units can’t communicate with one another, it will be unable to effectively balance indoor temperatures.

E5 – Voltage Protection or Temperature Sensor Error

If you own a mini split heat pump, an E5 error may indicate a problem with the system’s voltage. A repair technician from Marcos AC & Heating may refer to it as overcurrent protection. Both unusually 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 concerned with your mini splits compressor system, housed within the outdoor unit. When the compressor drive is not working, 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 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 rise above safe levels, a safety switch will 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 struggling with high or low pressure issues.

Consult the Manual for Your Specific Model

Keep in mind that in general, error codes are specific to each model of a Lennox mini split system. Your manual will provide a guide for these error codes and what they should mean. But since many of these codes refer to electrical problems, professional experience is usually necessary.

Call Marcos AC & Heating for Mini Split Repair

Marcos AC & Heating 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 unique 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 Houston, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 713-469-3357 today.