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.

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