Vaillant · Heat pumps · Vaillant aroTHERM plus with uniTOWER plus
F.785Fan unit 2: Fan blocked
Name in the manufacturer's documentation (service manual): Fan unit 2: Fan blocked
[1]
In plain words (editorial)
The second fan of the outdoor unit (fan unit 2) does not report that it is rotating – it may be blocked. The manual says to check the air route and remove any blockages.
When to call a service technician: If nothing visibly blocks the fan (e.g. snow, ice, leaves), contact a heating engineer.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Possible causes (source text)
- There is no confirmation signal stating that the fan is rotating[2]
Steps given by the manufacturer (source text)
- Check the air route and, if required, remove any blockages[3]
⚠ 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] Vaillant uniTOWER plus VIH QW 190/6 E – Operating, installation and maintenance instructions (0020291525_05) (0020291525_05) , p. 62 official manufacturer document quote verified
F.785 Fan unit 2: Fan blocked
- [2] Vaillant uniTOWER plus VIH QW 190/6 E – Operating, installation and maintenance instructions (0020291525_05) (0020291525_05) , p. 62 official manufacturer document quote verified
There is no confirmation signal stat- ing that the fan is rotating
- [3] Vaillant uniTOWER plus VIH QW 190/6 E – Operating, installation and maintenance instructions (0020291525_05) (0020291525_05) , p. 62 official manufacturer document quote verified
Check the air route and, if required, remove any blockages