150 on a NIBE heat pump: High condenser out / temporary HP alarm: Condenser out has reached max permitted temperature (VVM 310 service manual: temporary HP alarm, see alarm 50)
Short answer
On a NIBE heat pump, 150 means: High condenser out / temporary HP alarm: Condenser out has reached max permitted temperature (VVM 310 service manual: temporary HP alarm, see alarm 50). The heat pump keeps running.
Reviewed 23 September 2026 · 2 sources
What it means
The manuals for this range word it in different ways:
- High condenser out / temporary HP alarm: Condenser out has reached max permitted temperature (VVM 310 service manual: temporary HP alarm, see alarm 50).
- Sens flt from heat pump (BT17): Repeated sensor failures, suction gas sensor BT17 [other NIBE documents: Sensor fault, suction gas in F2050 (Tho-S) / Alarm generated by the heat pump: suction gas sensor fault].
Part involved: pressure switches/sensors, expansion valve; temperature/pressure sensor.
When it shows: Condenser out has reached max permitted temperature (VVM 310 service manual: temporary HP alarm, see alarm 50) Repeated sensor failures, suction gas sensor BT17; Sensor fault, suction gas in F2050 (Tho-S); Alarm generated by the heat pump: suction gas sensor fault.
Likely causes:
- S2060: Open/short circuit on sensor input; defective baseboard AA2 | F2050: Open/short circuit on sensor input; defective control board PWB1.
Is it safe?
| Does the heat pump stop? | No |
|---|---|
| Severity | Warning |
The heat pump keeps running.
Resetting itself: yes - Automatic reset.
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. Air source systems: check the outdoor unit is clear of leaves/snow/ice. Read the heating system pressure gauge and note the reading for your installer.
- 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 heating medium flow, particle filter and circulation pump; check pressure switches/sensors, expansion valve, service valves and refrigerant charge (F-gas qualified).
- Check sensor and its connections/wiring against the wiring diagram; measure sensor resistance against the NIBE temperature/resistance table; check the relevant PCB input. NIBE lists: Open/short circuit on sensor input; defective baseboard AA2; Open/short circuit on sensor input; defective control board PWB1.
Who to ask for: Heat pump engineer with F-gas qualification (NIBE-trained / NIBE PRO installer); NIBE-trained heat pump installer (NIBE PRO / VIP).
Certification: F-gas certification for refrigerant circuit work (plus flammable-refrigerant competence for R290/R32 models); Electrical work to BS 7671 by a competent person.
What you might notice
Sources
- ALARM LIST - NIBE products with Emmy display, Version 1747-1 (updated 2017-11-23) ↗ · 1747-1 · page 5 · Reviewed 23 September 2026
- Installer manual Air/water heat pump NIBE S2060 UK 1x230V IHB EN 2623-3 (831281) ↗ · IHB EN 2623-3 · page 31 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026