E54
Mitsubishi Heavy
Mitsubishi Heavy air conditioner error E54
Meaning
Low pressure sensor (PSL) disconnected/output error
General meaning for the brand's models, unless a model's own manual says otherwise.
How the unit shows it
- LED 1: Stays Off
- LED 2: Keeps Flashing
- LED 3: Flashes once
- LED 4: Keeps Flashing
Causes and how to check
- the cited manual page, and follow-up questions
No account needed to look up codes.
Guides
- Checking an air conditioner temperature sensor (thermistor)
How to check the room, coil or discharge sensor when the unit reports a sensor error: measure its resistance and compare with the exact model's table. - Pressure, low refrigerant and high discharge temperature errors: where to start
Pressure and discharge-temperature protection codes: tell a low charge from a blockage or poor heat rejection before charging.