BoilerFaultCodesYour boiler's internal valve is unable to switch between heating your radiators and providing hot water, likely because the motor controlling it has failed.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Actuator Head
What causes this fault?
This fault occurs when the small electric motor responsible for moving the internal valve becomes jammed or fails electrically. Over time, the internal components can wear out or become stuck due to debris in the heating water, preventing the boiler from switching between heating your home and warming your water.
This fault often becomes apparent during the first cold spell of autumn when the boiler is suddenly required to switch frequently between hot water and central heating modes.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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