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: Low Water Pressure - The system water pressure has fallen below 0.3 bar. Top up the system to 1.0 bar and the boiler will automatically reset.
What causes this fault?
This fault occurs when there isn't enough water inside your central heating system to allow the boiler to circulate heat safely. The most common reason is a slow leak from a radiator valve or pipework, but it can also happen if you have recently bled your radiators without topping the water back up.
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 your boiler.Slowly open the one or two taps on the loop until you hear water entering the system.Watch the pressure gauge and close the taps firmly when the needle reaches 1.0 bar.
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A boiler cover plan would cover faults like P — 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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