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 piece of HVAC equipment is flawless. There’s always a risk your mini-split could malfunction. To identify what went wrong, you’ll want to 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 required.

What the error 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 call the HVAC pros at B & B Heating & Cooling. Our technicians are trained to recognize these codes in order to ensure prompt mini-split repair in Florissant and St. Charles. Give us a call at 314-325-7552 to request an appointment.

Common Error Codes for Lennox Mini Splits

While error codes can differ from model to model, there are some codes you’ll be more likely to come across. To determine what your error code can mean, consider 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 indicates that communication between the mini-split system’s indoor and outdoor units has been disrupted. 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 B & B Heating & Cooling 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 could also stand for 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 might also be a problem 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 reason 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 make sure the indoor and outdoor units can communicate with one another. If the drive board is faulty, a P6 error code is common.

When temperatures rise above 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 issues.

Consult Your Service 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 should mean. But since many of these codes start with electrical problems, professional experience is typically necessary.

Trust B & B Heating & Cooling for Mini-Split Repair

B & B Heating & Cooling 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 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 Florissant and St. Charles, bringing your new system online with minimal comfort disruption.

To schedule an appointment, give us a call at 314-325-7552 today.