A07 on a Toshiba heat pump: Standard: pressure switch operation; Powerful: incorrect outdoor/hydro matching
Short answer
On a Toshiba heat pump, A07 means: Standard: pressure switch operation; Powerful: incorrect outdoor/hydro matching. 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 · 3 sources
What it means
On the Estia (Series 4) Standard & Powerful
The manual says: Standard: pressure switch operation; Powerful: incorrect outdoor/hydro matching.
Part involved: refrigerant charge, PMV, valves, pressure switch/sensor.
When it shows: Standard: pressure switch operates 300 s continuously; Powerful: system set-up mismatch.
Likely causes:
- Little or no water flow.
- Flow switch defect.
- Operation under heavy load.
- Pressure switch defect.
- DPSW13_4 setting (OFF = Standard, ON = Powerful).
On the Estia 5 Series (Standard)
The manual says: Pressure switch operation.
Part involved: refrigerant charge, PMV, valves, pressure switch/sensor.
When it shows: Pressure switch operates for 300 s continuously during heat pump operation.
Likely causes:
- Little or no water flow.
- Flow switch defect.
- Operation under heavy load.
- Pressure switch defect.
On the Estia 5 Series Powerful (Hi Power / Extreme)
The manual says: Combination error - model name of the hydro unit is different.
Part involved: DIP switches, DN/FC codes, addresses, model combination.
Likely causes:
- DP_SW13_4 must be set ON for the Powerful series.
Is it safe?
On the Estia (Series 4) Standard & Powerful
| 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.
On the Estia 5 Series (Standard)
| 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.
On the Estia 5 Series Powerful (Hi Power / Extreme)
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: no.
Manual reset: Cause must be fixed by an engineer; hardware faults reappear until repaired.
What you can check
On the Estia (Series 4) Standard & Powerful
- 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.
On the Estia 5 Series (Standard)
- 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.
On the Estia 5 Series Powerful (Hi Power / Extreme)
- Note the check code shown on the remote controller and the outdoor/hydro model numbers before contacting an engineer.
What the engineer will check
On the Estia (Series 4) Standard & Powerful
- Follow manufacturer's check-code flowchart.
- Little or no water flow.
- Flow switch defect.
- Operation under heavy load.
- Pressure switch defect.
- DPSW13_4 setting (OFF = Standard, ON = Powerful).
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 (Standard)
- Follow manufacturer's check-code flowchart.
- Little or no water flow.
- Flow switch defect.
- Operation under heavy load.
- Pressure switch defect.
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.
- DP_SW13_4 must be set ON for the Powerful series.
Who to ask for: Installer / commissioning engineer (Toshiba Estia).
Certification: Manufacturer training advantageous.
What you might notice
Sources
- Quick Reference Air to Water Heat Pump Series 4 Standard & Powerful Types ↗ · Quick Reference Series 4 Standard & Powerful (undated) · page p.60 (printed page; PDF page +1) · Reviewed 23 September 2026
- Air to Water Heat Pump Service Manual (File No. A10-1704) - Estia 5 Series Indoor/Outdoor ↗ · A10-1704 · page p.87 (printed page; PDF page +1) · Reviewed 23 September 2026
- Hydro Unit Installation Manual EF99812301-4 (Powerful) ↗ · EF99812301-4 · page p.57 (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