Lennox Mini Split Error Codes and What They Might Mean

October 25, 2021

Lennox mini split systems are an excellent way to provide compact, yet powerful 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 ductless mini split is flawless. There’s always a possibility your mini split could malfunction. To find out what went wrong, you’ll want to locate where the mini split error codes are displayed. Knowing what these codes mean can help you kickstart mini split repair, especially if professional help is needed.

What the error code means will ultimately depend on the specific model of your mini split system. You can review your manual to find a guide for what each code means. You can also call the HVAC pros at Aggressive Mechanical. Our technicians are trained to learn these codes in order to provide prompt mini split repair in Neptune City. Give us a call at 732-806-5536 to book 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 see. To determine 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 other signs of what is happening? A strange noise coming from an important component, for example.

Here are a handful 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 could 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 could indicate a problem with the system’s voltage. A repair technician from Aggressive Mechanical may refer to it as overcurrent protection. Both unusually high or low voltage can produce this error code.

For mini split air conditioners, this code can 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 might also be an issue with one of the temperature sensors.

P4 – Compressor Drive Error / High Temperature

A P4 error code will most times be related to your mini splits compressor system, housed within the outdoor unit. When the compressor drive is not working, the most likely cause is excessively high temperatures. A high temperature at the discharge line could 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 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 could appear. You may also find the P6 code if the compressor is struggling with high or low pressure concerns.

Consult the Manual for Your Specific Model

Remember that in general, error codes are different for each model of a Lennox mini split system. Your manual will offer a guide for these error codes and what they can mean. But because many of these codes start with electrical problems, professional experience is typically required.

Call Aggressive Mechanical for Mini Split Repair

Aggressive Mechanical can provide 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 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 Neptune City, bringing your new system online with little to no comfort disruption.

To schedule an appointment, give us a call at 732-806-5536 today.