BoilerFaultCodesYour boiler is struggling to read its internal water pressure correctly because the sensor is sending an unusual signal.
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 signal in the wrong range (too high)
What causes this fault?
This fault occurs when the boiler's internal sensor fails to provide a reliable reading of the water pressure, usually because the component has developed an electrical fault or is physically blocked by debris. The boiler enters a safety mode because it cannot confirm there is enough water inside to operate without damaging the heat exchanger. In some cases, this can also be caused by a communication issue in the wiring connecting the sensor to the main control board.
DIY fix possible
Check if the pressure gauge is above 2.5 bar and bleed a radiator to lower itTurn the boiler off and on again at the fused spur to reset the sensorEnsure the filling loop valves are fully closed
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A boiler cover plan would cover faults like F.74 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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