S5 on a Kensa heat pump: P5 pressure sensor error (discharge pipe)
Short answer
On a Kensa heat pump, S5 means: P5 pressure sensor error (discharge pipe). The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 4 sources
What it means
The manual says: P5 pressure sensor error (discharge pipe).
Part involved: P5 discharge transducer.
When it shows: Error level per manual: Fault.
Likely causes:
- P5 sensor faulty or disconnected.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: unknown.
What you can check
- Note the code shown on the controller/LED; check the heat pump isolator and consumer-unit breaker are on; check thermostat/timer settings.
What the engineer will check
- Follow Kensa fault table actions: P5 sensor faulty or disconnected.
Who to ask for: Refrigeration engineer (F-gas certified) / Kensa technical support.
Certification: F-gas Category I (refrigerant circuit work); MCS-certified GSHP installer.
What you might notice
Sources
- Kensa Evo Heat Pump Installation manual ↗ · V32 · page 52 · Reviewed 23 September 2026
- Q80 Series Heat Pump Operational Manual ↗ · Version 2 · page 25 · Reviewed 23 September 2026
- Shoebox Heat Pump Operational Manual (User Manual) ↗ · Version 8 · page 28 · Reviewed 23 September 2026
- Kensa Shoebox NX heat pump Installation manual ↗ · V12 · page 43 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026