BoilerFaultCodesYour boiler has detected that the water pressure is too low to operate safely and simply needs to be refilled with more water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low pressure. Requires ‘topping-up’
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to fire up safely. The most common reason is a tiny leak from a radiator valve or joint, though pressure also naturally drops if you have recently bled your radiators to remove air bubbles.
This issue is more frequent in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the one or two taps/valves on the filling loop until you hear water flowing.Watch the pressure gauge and close the taps firmly once the needle reaches between 1 and 1.5 bar.
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