20036 on a Stiebel Eltron WPM heat pump manager / WPMsystem: Temperature limiter for inverter of low pressure compressor has been triggered
Short answer
On a Stiebel Eltron heat pump, 20036 means: Temperature limiter for inverter of low pressure compressor has been triggered. 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: Temperature limiter for inverter of low pressure compressor has been triggered.
Part involved: compressor or fan inverter.
When it shows: Temperature limiter for inverter of low pressure compressor has been triggered.
Likely causes:
- Value is reset automatically. If necessary, clean the inverter heat sink.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: yes.
Manual reset: no.
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.
- Check the heating system pressure gauge reading is in the normal range stated by your installer.
What the engineer will check
- Value is reset automatically. If necessary, clean the inverter heat sink.
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 16 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026