Mitsubishi Electric · Heat pumps · Mitsubishi Electric Ecodan PUZ-WM outdoor unit (R32)
P8Pipe temperature
Name in the manufacturer's documentation (service manual): Pipe temperature
[1]
In plain words (editorial)
Pipe temperature abnormality after the compressor has been running. The service manual lists refrigerant leakage or shortage, the expansion valve, a clogged circuit or a detached thermistor holder.
When to call a service technician: Call a service technician with F-gas certification.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Detection conditions (source text)
- Abnormal if the following conditions are detected for continuously 3 minutes after compressor starts operating for 10 minutes[2]
Possible causes (source text)
Steps given by the manufacturer (source text)
⚠ Work on refrigerant circuits, mains electricity and PV DC wiring is for qualified technicians only.
The Polish page has more detail (plain-language explanation, safe checks, guides): Read in Polish →
Sources
Every statement has a footnote to the document and PDF page. “Quote verified” means the quote was found automatically in the text of that page.
- [1] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
- [2] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Abnormal if the following conditions are detected for continuously 3 minutes after compressor starts operating for 10 minutes
- [3] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Leakage or shortage of refrigerant
- [4] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Malfunction of linear expansion valve
- [5] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Refrigerant circuit is clogged with foreign objects
- [6] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Disconnection of thermistor holder
- [7] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Check intake superheat. Check leakage of refrigerant
- [8] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Check linear expansion valve
- [9] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
After recovering refrigerant, remove water from entire refrigerant circuit under vacuum more than 1 hour
- [10] Mitsubishi Electric – Service Manual: Air to water heat pump units, outdoor unit PUZ-WM50VHA … PUZ-WM112YAA (OCH727 REVISED EDITION-A, 12/2023) (OCH727A (12/2023)) , p. 31 official manufacturer document quote verified
Check the holder of thermistor