BoilerFaultCodesYour boiler has detected that the water pressure inside the system has dropped too low, which prevents it from igniting and heating your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Insufficient Water
DIY fix possible
Locate the external filling loop, usually two small valves connected by a silver braided hose under the boiler.Open the valves slowly to allow mains water into the heating system.Watch the boiler's pressure gauge until the needle reaches between 1.0 and 1.5 bar, then tightly close both valves.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 8.12 — no call-out fees, no surprises.
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Chaffoteaux Britony Duo 55 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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