30186 on a Stiebel Eltron WPM heat pump manager / WPMsystem: The heating circuit pump on the MFG cannot be switched
Short answer
On a Stiebel Eltron heat pump, 30186 means: The heating circuit pump on the MFG cannot be switched. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: The heating circuit pump on the MFG cannot be switched.
Part involved: bus/communication cabling.
When it shows: The heating circuit pump on the MFG cannot be switched.
Likely causes:
- Check the communication cable terminal or replace the communication cable.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: unknown.
Manual reset: unknown.
What you can check
- Read and note the full message code and time from the WPM display (DIAGNOSIS / NOTIFICATIONLIST if accessible without a code).
- Check the heat pump and controller circuit breakers/isolators at the consumer unit are on.
What the engineer will check
- Check the communication cable terminal or replace the communication cable.
Who to ask for: Heat pump service engineer (electrical/controls).
Certification: Qualified electrician competence for live-work on appliance electrics.
What you might notice
Sources
- WPM notification list (WPM V2.9) - multilingual; English section pp.15-26 (DOC-00081866) ↗ · WPM V2.9 · page 23 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026