Heat pumps · Error codes · Ariston
931-3Ariston · NIMBUS NET R32 control platform (shared error list)
931-3 on an Ariston NIMBUS NET R32 control platform: Inverter error sub-code 3: Inverter input voltage sensor error
Short answer
On an Ariston heat pump, 931-3 means: Inverter error sub-code 3: Inverter input voltage sensor error. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Inverter error sub-code 3: Inverter input voltage sensor error.
Part involved: inverter board / compressor drive.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: Parent code 931 is in the 'NO RESET' column (column interpretation from text extraction).
What you can check
- Note the error code shown on the Sensys HD interface and contact the installer / Ariston service.
- Check the consumer-unit breaker/isolator for the outdoor unit is on.
What the engineer will check
- Read the inverter sub-code and diagnose the inverter board/compressor per Ariston service instructions.
Who to ask for: heat pump engineer (inverter electronics).
Certification: Electrical competence.
What you might notice
Sources
- NIMBUS PLUS M NET R32 - Technical instructions for installation and maintenance (UK) - codes 3301719 3301720, doc 420000656201 EN ↗ · 420011311701 - 03/2024 · page 73 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026