BoilerFaultCodesYour boiler has detected that the water pressure is too low for the system to run safely and has stopped working to protect itself.
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 internal water pressure drops below the minimum level required for the boiler to circulate heat safely. The most common reasons are a slow leak somewhere in your radiator network or the need to top up the system after bleeding your radiators.
This issue is frequently seen in autumn when homeowners bleed their radiators for the first time or turn the heating back on after a long summer break.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open both small valves on the loop until you hear water moving and watch the pressure gauge.Close both valves tightly when the pressure needle reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like G — no call-out fees, no surprises.
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