BoilerFaultCodesYour boiler is temporarily pausing to check if there is enough water pressure before it starts up, which is preventing your heating and hot water from running.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water pressure sensor check is running, demand (DHW or heating) is blocked
What causes this fault?
This fault occurs when the boiler's internal computer tries to verify there is enough water pressure to run safely but fails to get a clear reading. The most common reason is a failing or blocked water pressure sensor that provides inconsistent data, causing the system to pause as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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