BoilerFaultCodesYour boiler has lost the ability to monitor its own water pressure, meaning it has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pressure sensor fault
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring water levels becomes blocked with debris or suffers an electrical failure. Over time, sludge in the heating system can coat the sensor's delicate diaphragm, preventing it from sending a clear signal to the main control board. Without this vital data, the boiler cannot confirm it has enough water to operate safely and will shut down to prevent overheating.
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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A boiler cover plan would cover faults like F74 — no call-out fees, no surprises.
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