BoilerFaultCodesTechnical description
DHW turbine debris, flow rates, diverter valve motor wiring, or diverter head engagement.
What causes this fault?
This issue occurs when the boiler fails to sense water moving through the pipes when you open a tap, often due to a small internal sensor being blocked by grit or debris. Alternatively, the internal 'shifting' valve may be physically stuck or the motor driving it has failed, meaning the heat stays trapped in the radiators instead of reaching your hot water outlets.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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