BoilerFaultCodesYour boiler is experiencing a pressure or flow issue with the cold water supply that feeds your hot water tank, meaning you likely have no hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Unvented Inlet Control Group
What causes this fault?
This fault occurs when the safety system detects an issue with the cold water entering your boiler's internal storage tank. It is usually caused by a failure of the inlet control valve, which manages the pressure of the incoming mains water to prevent the system from over-pressurising. If this valve becomes blocked or fails mechanically, the boiler shuts down the hot water production to prevent damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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