30209 on a Stiebel Eltron WPM heat pump manager / WPMsystem: Sensor value of "flow temperature sensor" outside the permissible range
Short answer
On a Stiebel Eltron heat pump, 30209 means: Sensor value of "flow temperature sensor" outside the permissible range. 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: Sensor value of "flow temperature sensor" outside the permissible range.
Part involved: temperature/pressure sensor.
When it shows: Sensor value of "flow temperature sensor" outside the permissible range.
Likely causes:
- Check sensor, leads and the relevant plug-in connectors, and replace if faulty. Terminal: WPM X1.5.
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 sensor, leads and the relevant plug-in connectors, and replace if faulty. Terminal: WPM X1.5.
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