BoilerFaultCodesYour boiler has failed to detect a rise in pressure when the pump started, meaning it cannot safely circulate water to heat your home.
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 boiler's internal computer doesn't see a small 'jump' in water pressure that should happen every time the pump kicks in. The most common reasons are a sensor blocked with debris or a failing pump that isn't moving the water with enough force to be detected.
This fault is more frequent in autumn when the heating is first turned on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check the pressure gauge on the front of the boilerIf the pressure is below 1.0 bar, use the filling loop to top it up to 1.5 barPress the 'Reset' button (indicated by a flame with a cross through it) to restart the boiler
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F.75 — 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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