Viessmann · Heat pumps · Viessmann Vitocal 250-A (One Base, monobloc)
A.99Flow temperature in secondary circuit downstream of condenser too low
Name in the manufacturer's documentation (service manual): Flow temperature in secondary circuit downstream of condenser too low
[1]
In plain words (editorial)
The flow temperature downstream of the condenser is too low; the refrigerant circuit switches off temporarily (condenser frost protection). The manual says no action is required.
When to call a service technician: No action needed unless the message keeps appearing – then contact 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. 71 manufacturer document – copy from a distributor quote verified
A.99
- [2] Viessmann – Service instructions: System configuration and diagnosis for heat pumps with Viessmann One Base (6194799 GB, 3/2022) (6194799 GB (3/2022)) , p. 71 manufacturer document – copy from a distributor quote verified
no action required
- [3] Viessmann – Service instructions: System configuration and diagnosis for heat pumps with Viessmann One Base (6194799 GB, 3/2022) (6194799 GB (3/2022)) , p. 71 manufacturer document – copy from a distributor quote verified
refrigerant circuit temporarily