H06.01 on a Baxi heat pump: HP Unit Failure Heat Pump Unit Failure occured
Short answer
On a Baxi heat pump, H06.01 means: HP Unit Failure Heat Pump Unit Failure occured. 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 · 2 sources
What it means
On the Assure Split ASHP (AWHP 4.5/6/8 MR + Assure AWHP-IDU 4-8 E)
The manual says: HP Unit Failure Heat Pump Unit Failure occured.
Part involved: PCB communication wiring.
Likely causes:
- Heat pump outdoor unit fault Check the wiring between the central unit PCB and the communication bus on the outdoor unit. Check the connection of the communication cable between the central unit PCB and the interface PCB. Check the connection of the supply cable between the central unit PCB and the interface PCB. Check the connection of the outdoor unit supply cable.
On the HP60 / Baxi Assure HP55 High Temperature Monobloc ASHP (R290)
The manual says: HP Unit Failure Heat Pump Unit Failure occurred.
Part involved: PCB communication wiring.
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
On the Assure Split ASHP (AWHP 4.5/6/8 MR + Assure AWHP-IDU 4-8 E)
- Heat pump outdoor unit fault Check the wiring between the central unit PCB and the communication bus on the outdoor unit. Check the connection of the communication cable between the central unit PCB and the interface PCB. Check the connection of the supply cable between the central unit PCB and the interface PCB. Check the connection of the outdoor unit supply cable.
Who to ask for: heat pump engineer (controls / sensors).
Certification: Manufacturer-trained heat pump engineer.
On the HP60 / Baxi Assure HP55 High Temperature Monobloc ASHP (R290)
- Diagnose per manufacturer service procedure (manual gives description only).
Who to ask for: heat pump engineer (controls / sensors).
Certification: Manufacturer-trained heat pump engineer.
What you might notice
Sources
- Installation and Service Manual - Air/water 'Split Inverter' heat pump Baxi Assure, Assure AWHP-IDU 4-8 E ↗ · 7762758 - v05 - 19082020 · page 91 · Reviewed 23 September 2026
- Installation, user and service manual - Indoor unit ASHP Control ↗ · 7887625 - v04 - 22072025 · page 128 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026