BoilerFaultCodesYour boiler has lost its ability to accurately measure water pressure, which prevents it from running safely.
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 fault
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read a consistent signal from the water pressure sensor. The most common reason is that the sensor itself has developed an electrical failure or has become blocked with system debris, preventing it from detecting if there is enough water to operate safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E78 — 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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