Heat pumps · Error codes · Riello
81Riello · NXHP (R290 monobloc)
81 on a Riello NXHP: Inverter fault - stator over heat
Short answer
On a Riello heat pump, 81 means: Inverter fault - stator over heat. 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 fault - stator over heat.
Likely causes:
- Manual: investigations and corrective actions to be performed by a fully qualified technician (see Table 6 probable causes).
Is it safe?
Switch the heat pump off at its isolator and call an engineer.
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
What you can check
- Read and note the exact code shown on the controller display.
- Check the heat pump's breaker/isolator at the consumer unit is on.
- If the breaker has tripped or trips again, leave the unit off and call an engineer; do not keep resetting it.
What the engineer will check
- Manual: investigations and corrective actions to be performed by a fully qualified technician (see Table 6 probable causes).
Sources
- Riello NXHP Series Installation, Operation and Maintenance Instructions (ManualsLib copy) ↗ · not stated · page 68 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026