Mitsubishi Heavy Air Conditioning Repair & E55 Fault Fix in Walsall

E55 Fault Diagnosis & Sensor Replacement

Location: Walsall, West Midlands

Swipe

Diagnosing a Mitsubishi Heavy AC Fault in Walsall
A commercial gym in Walsall recently contacted ACRC LTD, reporting that their main air conditioning unit had stopped working. Upon arriving at the site, our engineers quickly identified that the Mitsubishi Heavy A/C unit was displaying an E55 Fault code.

Tracing the E55 Fault Code
An E55 fault specifically refers to the “compressor under dome thermistor being disconnected.” To find the root cause, our team meticulously traced the thermistor cables back to the PCB. We discovered that the cables had been chewed apart outside—likely by pests—causing a complete break in the connection. The system was safely isolated, and an exact replacement sensor was immediately ordered.

Sensor Replacement & Preventative Care
Once the new sensor arrived, we unplugged the damaged component and fitted the replacement. The unit was turned back on, immediately clearing the fault codes and returning the system to normal operation. To ensure optimal performance, we checked the air-off temperatures and monitored the refrigerant pressures, leaving the unit at the customer's requested setting.

To prevent rodents or pests from causing similar damage in the future, we also offer the installation of a custom metal plate to seal off the pipe hole entry, thoroughly protecting the external wiring from future risks.

Expert Commercial Fault Finding
If your commercial or domestic system is displaying a fault code or not working correctly, call us today for a FREE quote. Our fully qualified air conditioning engineers have years of diagnostic experience and are always happy to help get your business back up and running.