H06.65 on a Baxi HP60 / Baxi Assure HP55 High Temperature Monobloc ASHP: HP high temp cooling HP refrigerant outlet temperature is too high in cooling mode
Short answer
On a Baxi heat pump, H06.65 means: HP high temp cooling HP refrigerant outlet temperature is too high in cooling mode. 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: HP high temp cooling HP refrigerant outlet temperature is too high in cooling mode.
Part involved: refrigerant pressure / temperature.
Likely causes:
- The heat exchanger cover has not been taken off. Remove it. The heat exchanger is dirty or clogged. Clean the exchanger. There is insufficient space around the unit for heat exchange. The fan motor is broken, replace it.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: yes - system restarts automatically when the cause disappears (may run in degraded/back-up mode meanwhile).
Manual reset: not required once cause removed.
What you can check
- Note the exact code shown on the controller and when it appeared.
- Check the outdoor unit is not blocked by leaves, debris, snow or covers and has clear airflow.
- The manual's user steps allow switching the system off and on once to see if the error clears; if the code returns, contact the installer.
- If the code persists or returns, contact a heat pump engineer.
What the engineer will check
- The heat exchanger cover has not been taken off. Remove it. The heat exchanger is dirty or clogged. Clean the exchanger. There is insufficient space around the unit for heat exchange. The fan motor is broken, replace it.
Who to ask for: heat pump / refrigeration engineer (F-gas).
Certification: F-gas certification (Category I) for refrigerant work; competence with flammable A3 refrigerant R290.
What you might notice
Sources
- Installation, user and service manual - Indoor unit ASHP Control ↗ · 7887625 - v04 - 22072025 · page 132 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026