BoilerFaultCodesTechnical description
DHW sensor out of range. DHW sensor measures a temperature outside normal working range.
What causes this fault?
This fault occurs when the electrical voltage entering the boiler drops below the minimum level required for its electronic components to function correctly. The most common reason is an instability in your home's mains power supply or a loose connection within the boiler's internal wiring that is restricting the flow of electricity. In some cases, the boiler's main control board may be incorrectly detecting a drop in power due to a failing internal sensor.
This issue can be more frequent during periods of extreme weather or high local energy demand, which can cause temporary fluctuations or 'brownouts' in the national grid supply.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.