If an E6 error code displays on a mini split there are a few things a DIY type person can do before calling an HVAC tech.
Of course if in doubt always call a professional.
Below are the steps to troubleshoot and fix an E6 error code.
You will need to know how to use a multi meter for checking voltages and continuity.
What is an E6 error Code on a Mini Split
An E6 error code is a communication error that the inside unit is not able to communicate with the outside unit.
This includes the high voltage and low voltage lines.
What Causes an E6 Code on a Mini Split
The most common cause of an E6 error is the communication wires between the inside and outside units.
This includes the voltage at the outside unit (115/230) and the voltage going to the inside unit.
Most all mini split units have high voltage going to the outside unit which sends a lower voltage to the inside unit.
There is also a 4-8 wire communication line between each unit, all of which will need to be checked for a bad connection or an open in a wire.
If all the wiring and voltages are good the likely problem will be the one of the control boards on the inside or outside units.
Steps to Troubleshoot and Fix an E6 code
Voltages will vary between mini split units. A schematic will be on the inside door of both the indoor and outdoor units.
- First check the voltage on the outside unit.
- Check the voltage on the inside unit.
- Check the communication signal wires between the inside and outside units for bad connection or an open wire.
- A common method to check the wires for an open is to turn off all power to the system, cross two wires, and check them on the other side for continuity with a meter.
- If the voltages are correct and comuncaiton line good the problem is most likely a bad control board on the inside or outside unit.
Above is the basic steps a homeowner can do to fix an E6 error code.
The problem usually is in the voltage or communication lines.
Keep in mind bad wiring can damage a control board with both needed to be replaced in some scenarios.
If all the communication wiring and voltages test good the problems is most likely a bad control board.
At that point it would be best to call an HVAC tech to fix the unit.