52 on a NIBE heat pump: The temperature limiter has tripped: Temperature limiter has tripped [other NIBE documents: Temperature limiter deployed and open for more than 30 s]
Short answer
On a NIBE heat pump, 52 means: The temperature limiter has tripped: Temperature limiter has tripped [other NIBE documents: Temperature limiter deployed and open for more than 30 s]. 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 temperature limiter has tripped: Temperature limiter has tripped [other NIBE documents: Temperature limiter deployed and open for more than 30 s].
Part involved: temperature limiter / anode.
When it shows: Temperature limiter has tripped; Temperature limiter deployed and open for more than 30 s.
Likely causes:
- See fault-tracing schedule (SM p.46).
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: no/unknown - Internal electrical addition is blocked; None (handled by hardware).
Manual reset: Reset from the controller alarm menu ('reset alarm' / 'Reset alarm and try again'); alarm recurs if the cause remains.
What you can check
- Read the alarm text and the 'info/action' help on the controller display (VVM/SMO or S-series smartguide). NIBE's manuals let the homeowner select 'reset alarm' ('Reset alarm and try again' on S-series); if the lamp returns to normal the alarm has cleared. If it comes back, do not keep resetting: select 'aid mode' ('Auxiliary operation' on S-series) if offered, so any electric additional heat keeps heat/hot water going, and contact your installer.
What the engineer will check
- Check temperature limiter (reset button inside unit), immersion heater and electrical anode circuit. NIBE lists: See fault-tracing schedule (SM p.46).
Who to ask for: NIBE-trained heat pump installer (NIBE PRO / VIP).
Certification: None specific beyond competent heat pump installer; electrical work to BS 7671.
What you might notice
Sources
- Service manual NIBE VVM 310 Indoor module SEM GB 1451-1 (M11741) ↗ · SEM GB 1451-1 · page 16 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026