Skip to content
EN

Mitsubishi Electric · Heat pumps · Mitsubishi Electric Ecodan PUZ-WM outdoor unit (R32)

E9Indoor/outdoor unit communication error (transmitting error, outdoor unit)

Name in the manufacturer's documentation (service manual): Indoor/outdoor unit communication error (transmitting error, outdoor unit)[1]

In plain words (editorial)

Communication error between the indoor and outdoor units – the outdoor board cannot transmit. The service manual lists a contact failure of the connecting wire or electrical noise.

When to call a service technician: Have the installer check the connecting wire.

✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.

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. [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. 30 official manufacturer document quote verified
  2. [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. 30 official manufacturer document quote verified Abnormal if outdoor controller circuit board could not find blank of transmission path for 3 minutes
  3. [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. 30 official manufacturer document quote verified Indoor/ outdoor unit connecting wire has contact failure
  4. [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. 30 official manufacturer document quote verified Noise has entered power supply
  5. [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. 30 official manufacturer document quote verified Noise has entered indoor/ outdoor unit connecting wire
  6. [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. 30 official manufacturer document quote verified Check disconnection or looseness of indoor/ outdoor unit connecting wire
  7. [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. 30 official manufacturer document quote verified Replace outdoor controller circuit board if abnormality is displayed again