Vokèra · Vision, Compact A and Unica A-code platform
A06Domestic hot-water thermistor fault
This code applies to Vision 25C, Vision 30C, Compact A, Unica 28i, Unica 32i. Fault codes narrow down the likely problem, but they do not replace a model-specific diagnosis.
What you can safely check
- No internal homeowner repair is safe for this fault.
- A single reset may be tried only where the model's user manual allows it.
- Arrange an engineer if the code remains or returns.
How an engineer may fix it
Test the relevant sensor or thermistor, its position, resistance, plug and wiring; repair the connection or replace the failed sensor and verify operation.
Some status codes apply only to certain variants. Confirm the exact user manual.
Manufacturer source: Vokèra — Vision Combi 25C/30C User, Installation and Servicing Manual. Checked 15 August 2026. The appliance manual and an engineer’s on-site diagnosis take precedence. Never remove the boiler case yourself.