BoilerFaultCodesYour boiler has detected that the water pressure is too high, which has caused it to stop working to protect the internal components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault: Water press. sensor (signal too strong) - Water pressure too high
What causes this fault?
This fault occurs when the boiler's internal sensor detects that the water pressure has exceeded safe operating limits, often due to the system being overfilled via the filling loop. It can also be caused by a failing expansion vessel that can no longer absorb the natural pressure increase that happens when your heating warms up.
This fault is more common in autumn when homeowners top up their boiler pressure for the first time before winter and accidentally add too much water.
DIY fix possible
Locate a radiator and use a bleed key to release a small amount of water into a cloth or container.Monitor the pressure gauge on the boiler control panel as you release water.Stop bleeding the radiator once the pressure gauge returns to the green zone (usually 1.0 to 1.5 bar) and restart the boiler.
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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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