BoilerFaultCodesYour boiler has stopped working because the water pressure in the central heating system is too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: CH system pressure less than 0.5 bar or faulty water pressure switch.
What causes this fault?
This fault occurs when there isn't enough water circulating through your pipes and radiators to allow the boiler to operate safely. The most common reason is a slow leak somewhere in the system or because you recently bled your radiators, which lowers the overall pressure. In some cases, the internal expansion vessel may have lost its charge, causing water to escape through the safety valve.
This fault is more common in autumn when homeowners turn their heating back on for the first time after summer, revealing pressure losses that occurred while the system was idle.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath or near the boiler.Open the black taps on the filling loop slowly until you hear water flowing.Close both taps tightly once the pressure gauge on the boiler 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 E10 — 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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