Alpha · E-Tec Plus
06Domestic hot-water sensor fault
This code applies to E-Tec Plus 28, E-Tec Plus 33, E-Tec Plus 38. 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.
Manufacturer source: Alpha Heating Innovation — E-Tec Plus Installation and Servicing Instructions (01/22). Checked 15 August 2026. The appliance manual and an engineer’s on-site diagnosis take precedence. Never remove the boiler case yourself.