Mitsubishi Ecodan fault codes explained

Mitsubishi Ecodan heat pumps show a fault code when something needs attention. Some are minor and clear themselves, others need an engineer. Here is a plain-English overview of the ones we see most often on Ecodan systems across Scotland.

Where to find the code

The code shows on the FTC controller display, usually as a letter and number. Note it down before you do anything else, as it tells the engineer exactly where to look and saves diagnosis time.

Common codes and what they mean

Flow and temperature codes often relate to a stuck pump, trapped air or a closed valve. Refrigerant and pressure codes point to the outdoor unit and should not be ignored. Communication codes usually mean a wiring or controller issue.

What you can try, and what needs an engineer

You can safely check for obvious causes like isolated power or closed valves and note the code. Anything involving refrigerant, the compressor or persistent faults needs a qualified engineer. We repair Ecodan and read the full code history.