Mitsubishi Electric · Heat pumps · Mitsubishi Electric Ecodan FTC7 controller (PUZ-WM/WZ, PUHZ-SW)
L4DHW tank water temperature overheat protection
Name in the manufacturer's documentation (service manual): DHW tank water temperature overheat protection
[1]
In plain words (editorial)
Overheat protection of the hot water (DHW) tank has tripped. The manual says to check the immersion heater and its contactor.
When to call a service technician: The immersion heater and contactor are checked by the installer – they are mains-powered.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Steps given by the manufacturer (source text)
- Check the immersion heater and it’s contactor[2]
⚠ 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 Ecodan FTC7 PAC-IF081B-E / PAC-IF082B-E / PAC-IF083B-E – Installation Manual (DG79H200H02) , p. 33 official manufacturer document quote verified
L4 DHW tank water temperature overheat protection
- [2] Mitsubishi Electric Ecodan FTC7 PAC-IF081B-E / PAC-IF082B-E / PAC-IF083B-E – Installation Manual (DG79H200H02) , p. 33 official manufacturer document quote verified
Check the immersion heater and it’s contactor