BoilerFaultCodesYour boiler has stopped working because the water pressure in the central heating system has dropped too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System pressure too low
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to operate safely. The most common reason is a slow leak from a radiator valve or joint, though pressure can also drop if you have recently bled your radiators and haven't topped the water back up.
This code often appears in autumn when homeowners turn their heating back on for the first time or bleed their radiators to remove air pockets.
DIY fix possible
Locate the filling loop (the silver flexible hose usually found under the boiler).Open the small black valves slowly until you hear water flowing.Watch the pressure gauge and close the valves once it reaches between 1.0 and 1.5 bar.
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A boiler cover plan would cover faults like E118 — 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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