Mitsubishi Electric U3

Medium

Mr. Slim — Discharge thermistor (outdoor) open/short.

Mitsubishi Electric U3: Discharge thermistor (outdoor) open/short. This fault usually isn't an immediate stop, but should be checked soon.

Possible causes

Thermistor faulty / connector loose.

Check steps

Check discharge thermistor & connector.
Check resistance per service manual.

Affected parts

Heißgas-Thermistor

Safety note

Mind hot discharge side.

Source: Mitsubishi Electric resmi servis kılavuzu — MrSlimerrorCode.pdf p.4: 'U3, U4 Open/short of outdoor unit thermistors'; PUY doc p.9: 'Open/short of discharge thermistor (TH4) and comp. surface thermistor (TH32/33)'.

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

Look up in Enthalio →

Related fault codes

Indoor/outdoor communication error.E6 High discharge temperature — compressor overheU2 Outdoor thermistor fault (open/short).U4 Pipe temperature error (often defrost/thermistP8 Intake (room) thermistor fault.P1 Pipe (liquid) thermistor fault.P2