H06.25 on a Baxi HP60 / Baxi Assure HP55 High Temperature Monobloc ASHP: Tflow heat pump Heat pump flow temperature sensor error
Short answer
On a Baxi heat pump, H06.25 means: Tflow heat pump Heat pump flow temperature sensor error. 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: Tflow heat pump Heat pump flow temperature sensor error.
Part involved: temperature sensor.
Likely causes:
- Check the wiring between the EHC–16 PCB and the sensor. Check that the sensor has been fitted properly. Check the Ohmic value of the sensor. Replace the sensor if necessary.
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.
- 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
- Check the wiring between the EHC–16 PCB and the sensor. Check that the sensor has been fitted properly. Check the Ohmic value of the sensor. Replace the sensor if necessary.
Who to ask for: heat pump engineer (controls / sensors).
Certification: Manufacturer-trained heat pump engineer.
What you might notice
Sources
- Installation, user and service manual - Indoor unit ASHP Control ↗ · 7887625 - v04 - 22072025 · page 129 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026