BoilerFaultCodes MAIN BURNER DOES NOT LIGHT High
Your boiler is failing to ignite the main flame, which means you currently have no heating or hot water because the system cannot produce heat safely.
Call an engineer soon
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: I) Gas service tap not open fully; II) Gas pressure low; III) Water rate low; IV) Gas valve not opening; V) Diaphragm punctured; VI) Venturi blocked or loose; VII) Gas control tap faulty; VIII) Wrong injector; IX) Slow ignition device stuck or wrongly adjusted
Typical repair cost £150-350 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 MAIN BURNER DOES NOT LIGHT — no call-out fees, no surprises.
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Chaffoteaux Britony II 50FF 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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