F24 on a Toshiba heat pump: PD sensor failure
Short answer
On a Toshiba heat pump, F24 means: PD sensor failure. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 23 September 2026 · 2 sources
What it means
On the R32 Estia 1-Series (split, Wall-Mounted and All-in-One)
The manual says: PD sensor failure.
Part involved: refrigerant charge, PMV, valves, pressure switch/sensor.
When it shows: Open or short circuit in high pressure sensor PD.
Likely causes:
- PD value via remote controller.
- PD sensor connection.
On the Estia 5 Series Powerful (Hi Power / Extreme)
The manual says: PD sensor error.
Part involved: refrigerant charge, PMV, valves, pressure switch/sensor.
Likely causes:
- PD sensor value via remote controller.
Is it safe?
| 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 outdoor unit is not blocked by leaves, debris, snow or ice, and that nothing is covering the air inlet/outlet.
What the engineer will check
On the R32 Estia 1-Series (split, Wall-Mounted and All-in-One)
- Follow manufacturer's check-code flowchart.
- PD value via remote controller.
- PD sensor connection.
Who to ask for: F-gas certified refrigeration / heat pump engineer.
Certification: F-gas Category I; R32 is A2L mildly flammable - trained handler required.
On the Estia 5 Series Powerful (Hi Power / Extreme)
- Follow manufacturer's check-code flowchart.
- PD sensor value via remote controller.
Who to ask for: F-gas certified refrigeration / heat pump engineer.
Certification: F-gas Category I; R32 is A2L mildly flammable - trained handler required.
What you might notice
Sources
- Air to Water Heat Pump Service Manual - Wall Mounted Type (File No. AE0-2101W) ↗ · AE0-2101W · page p.115 (printed page; PDF page +1) · Reviewed 23 September 2026
- Hydro Unit Installation Manual EF99812301-4 (Powerful) ↗ · EF99812301-4 · page p.59 (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