1F on a Viessmann Vitotronic 200: Parameter "Output compressor stage 5030" not set correctly
Short answer
On a Viessmann heat pump, 1F means: Parameter "Output compressor stage 5030" not set correctly. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Parameter "Output compressor stage 5030" not set correctly.
Part involved: Parameter "Output compressor stage 5030" not set correctly.
When it shows: No type given. Heat pump characteristics: Compressor OFF No type given. Heat pump characteristics: Both compressors OFF.
Likely causes:
- Parameter "Output compressor stage 5030" not set correctly.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Information only |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: Not stated in 6150133.
Manual reset: Refrigerant circuit messages cannot be acknowledged in the message history (6150133 p.155); acknowledge the resulting 05/07/A9 message on the control unit.
What you can check
- This code is only visible to engineers in the service menu (Diagnosis > Refrigerant circuit > Message history); homeowners see message 05, 07 or A9 - note that code and call your contractor.
What the engineer will check
- Set "Output compressor stage 5030" according to the type plate. Then switch off the heat pump control unit. Wait 1 min. Then restart the heat ….
Who to ask for: Viessmann-trained heat pump engineer with F-gas refrigeration certification.
Certification: F-gas certificate (UK F-gas Regulations; Viessmann: refrigerant work by authorised refrigeration engineers only).
What you might notice
Sources
- Service instructions Vitotronic 200 type WO1C heat pump control unit (air/water split & monobloc, brine/water) (6150133, 2023-07) ↗ · 6150133 VSA00004 · pages 167, 173, 180 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026