BoilerFaultCodesYour boiler has lost its water pressure, which means it has stopped running to protect the internal components from damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Indicates 0 bar pressure in the system on the display
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to operate safely. It is usually caused by a small leak in the pipework or radiators, or because air was recently bled from the system without being topped back up.
This issue is more common in autumn when homeowners turn their heating back on for the first time, exposing small leaks or air pockets that developed over the summer.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) under the boiler.Slowly open the one or two small taps on the hose until you hear water flowing.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the taps tightly.
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 0 bar — no call-out fees, no surprises.
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Glow-worm Xtrafast 96 120 is discontinued — time for a new one?
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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