A14 on a Toshiba R32 Estia 1-Series: Pump failure

What it means

The manual says: Pump failure.

Part involved: circulation pump, flow switch/sensor, strainer, water pipework.

When it shows: Built-in pump stopped (causes other than low voltage, e.g. lock).

Likely causes:

• Pump locked by dirt/clogging.
• Humidity/condensation on pump electrics.
• Low supply voltage.

Is it safe?

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 system pressure gauge on the hydro unit / heating system shows the normal fill pressure the installer set (the manuals ask for at least about 1 bar); if it is low, report it to the engineer. Check the filling loop is closed.
• Check radiator/underfloor zone valves and thermostats are calling for heat and have not all been turned off.

What the engineer will check

• Follow manufacturer's check-code flowchart.
• Pump locked by dirt/clogging.
• Humidity/condensation on pump electrics.
• Low supply voltage.

Who to ask for: Heat pump / heating engineer (hydronic).

Certification: Heat pump installer competence (e.g. MCS-installer staff); no F-gas needed unless refrigerant work follows.

What you might notice

• Check code shown on the remote controller (buzzer sounds); heating and/or hot water stops or runs on backup electric heater only.

Sources

• Air to Water Heat Pump Service Manual - Wall Mounted Type (File No. AE0-2101W) ↗ · AE0-2101W · page p.112; IM printed p.33 (pump lock) (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