BoilerFaultCodesYour boiler has detected that the water pressure in the central heating system is too low to operate safely and effectively.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low system pressure
What causes this fault?
This fault occurs when the water level inside your central heating system drops below the minimum required for the boiler to heat up safely. 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 often surfaces at the start of autumn when the heating is turned on for the first time after summer, as stagnant seals may weep or air pockets shift within the system.
DIY fix possible
Locate the filling loop (usually a silver flexible hose with small valves under the boiler).Slowly open the valve(s) until you hear water flowing and watch the pressure gauge.Close the valves tightly once the pressure gauge reaches between 1.0 and 1.5 bar.
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A boiler cover plan would cover faults like 0.0 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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