BoilerFaultCodesYour boiler has stopped working because the water pressure is too low and needs to be topped up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pressure needs filling to < 0.5 bar
What causes this fault?
This fault occurs because the internal water pressure has dropped below the minimum level required for the boiler to operate safely. The most common reason is a slow leak somewhere in your radiator system or air being released through the valves, but it can also happen if the expansion vessel inside the boiler has lost its charge.
This issue is more frequent during the autumn and winter months when the heating is first turned back on after summer, as the change in temperature can highlight existing minor leaks or air pockets.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath your boiler.Open the valves slowly until you hear water entering the system.Watch the pressure gauge and close the valves once it reaches between 1.2 and 1.5 bar.
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A boiler cover plan would cover faults like 108 — 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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