BoilerFaultCodesYour boiler has detected that the water pressure is too low, causing it to shut down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: LOW WATER PRESSURE
What causes this fault?
This fault occurs when the system loses the physical water pressure required to circulate heat effectively through your pipes and radiators. The most common reasons are a slow leak hidden somewhere in the central heating circuit or the natural loss of pressure that happens after you bleed your radiators.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for the cold weather.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Open the one or two taps/valves slightly until you hear water entering the system.Watch the pressure gauge and close the taps once the needle reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like H — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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