Heat pumps · Error codes · Haier
H2Haier · HPM-Nd2 monobloc (R290, Haier Water Heater Co.)
H2 on a Haier HPM-Nd2 monobloc: Liquid pipe temperature sensor failure
Short answer
On a Haier heat pump, H2 means: Liquid pipe temperature sensor 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: Liquid pipe temperature sensor failure.
Part involved: temperature/pressure sensor.
Likely causes:
- Temperature sensor damaged, miswired.
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
- Installation and service instructions - HPM08/10/12/14/16-Nd2 (Haier R290 monobloc) ↗ · page p.85 (printed; ManualsLib viewer p.91) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026