Heat pumps · Error codes · Baxi
A02.37Baxi · Assure Split ASHP (AWHP 4.5/6/8 MR + Assure AWHP-IDU 4-8 E)
A02.37 on a Baxi Assure Split ASHP: Uncritic device lost Uncritical device has been disconnected:
Short answer
On a Baxi heat pump, A02.37 means: Uncritic device lost Uncritical device has been disconnected:. The heat pump keeps running. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Uncritic device lost Uncritical device has been disconnected:.
Part involved: PCB communication wiring.
Likely causes:
- Bad connection: check the wiring and connectors. Faulty SCB PCB: replace SCB PCB.
Is it safe?
| Does the heat pump stop? | No |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The heat pump keeps running.
Resetting itself: yes - may disappear spontaneously if conditions improve.
Manual reset: not required.
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
- Bad connection: check the wiring and connectors. Faulty SCB PCB: replace SCB PCB.
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 94 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026