BoilerFaultCodesYour boiler has stopped working because the water pressure is too low for it to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: insufficient water pressure in the heating system
What causes this fault?
This fault occurs when the water level inside your central heating system drops below the minimum level required to operate. The most common reason is a slow leak from a radiator valve or pipework, though it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This issue is more frequent in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Locate the filling loop (the silver braided hose beneath the boiler).Slowly open the one or two taps on the hose until you hear water flowing.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the taps fully.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F.22 — 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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