P02 on a Toshiba R32 Estia 1-Series: Converter circuit failure
Short answer
On a Toshiba heat pump, P02 means: Converter circuit failure. 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: Converter circuit failure.
Part involved: mains supply, inverter board.
When it shows: Converter circuit fault (3-phase models).
Likely causes:
- Supply voltage/frequency (380-415V +-10%, 50Hz +-5%).
- Replace outdoor board MCC-1780.
Is it safe?
Switch the heat pump off at its isolator and call an engineer.
| 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.
Manual reset: Cause must be fixed by an engineer; hardware faults reappear until repaired.
What you can check
- Note the check code shown on the remote controller and the outdoor/hydro model numbers before contacting an engineer.
- Check the consumer-unit breakers/isolators for the outdoor unit, hydro unit and backup heater are switched on.
What the engineer will check
- Follow manufacturer's check-code flowchart.
- Supply voltage/frequency (380-415V +-10%, 50Hz +-5%).
- Replace outdoor board MCC-1780.
Who to ask for: Heat pump engineer with electrical competence.
Certification: Electrical competence (Part P / 18th Edition).
What you might notice
Sources
- Air to Water Heat Pump Service Manual - Wall Mounted Type (File No. AE0-2101W) ↗ · AE0-2101W · page p.116 (printed page; PDF page +1) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026