BoilerFaultCodesYour boiler's internal sensor is struggling to accurately read the water pressure, which prevents the system from operating 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 electronic sensor can no longer accurately monitor the water pressure inside the system. The most common reason is that the sensor has suffered an electrical failure or has become blocked by debris and sludge build-up, preventing it from sending a reliable signal to the main control board.
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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