Viessmann · Heat pumps · Viessmann Vitocal 250-A (One Base, monobloc)
A.70Filter in ball valve of outdoor unit is contaminated
Name in the manufacturer's documentation (service manual): Filter in ball valve of outdoor unit is contaminated
[1]
In plain words (editorial)
The filter in the ball valve of the outdoor unit is contaminated, so the flow rate is too low. The manual's action: clean that filter.
When to call a service technician: If you are unsure how to do it, ask your heating contractor.
✎ 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] Viessmann – Service instructions: System configuration and diagnosis for heat pumps with Viessmann One Base (6194799 GB, 3/2022) (6194799 GB (3/2022)) , p. 69 manufacturer document – copy from a distributor quote verified
A.70
- [2] Viessmann – Service instructions: System configuration and diagnosis for heat pumps with Viessmann One Base (6194799 GB, 3/2022) (6194799 GB (3/2022)) , p. 69 manufacturer document – copy from a distributor quote verified
clean the filter in the outdoor unit
- [3] Viessmann – Service instructions: System configuration and diagnosis for heat pumps with Viessmann One Base (6194799 GB, 3/2022) (6194799 GB (3/2022)) , p. 69 manufacturer document – copy from a distributor quote verified
flow rate too low