Heat pumps · Error codes · Haier
28Haier
28 on a Haier heat pump: High pressure sensor failure
Short answer
On a Haier heat pump, 28 means: High pressure sensor failure. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 2 sources
What it means
The manual says: High pressure sensor failure.
Part involved: temperature/pressure sensor.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: unknown.
What you can check
- Note the code shown on the controller and the unit model numbers (on the rating plate label) before contacting your installer.
- Check the heat pump's breaker/isolator at the consumer unit is on; do not open any casing.
- Check the controller display is lit; a single power cycle at the isolator may be tried only if your installer or manual allows it.
What the engineer will check
- Follow the manufacturer's troubleshooting flowchart for this code.
- Check sensor connector and wiring.
- Measure sensor resistance against the manual's sensor table.
- Replace sensor or PCB as indicated by the troubleshooting flowchart.
Who to ask for: Heat pump engineer.
Certification: Heat pump installer competence; F-gas / flammable-refrigerant (R290/R32) handling competence for any refrigerant-circuit work.
What you might notice
Sources
- ATW Service Manual (Super Aqua monobloc) SYJS-03-2019 REV.A ↗ · SYJS-03-2019 REV.A · page p.73 (printed; PDF p.75) · Reviewed 23 September 2026
- Haier HU062WAMNA Service Manual (Super Aqua split R32) ↗ · page p.122 (printed = ManualsLib viewer page) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026