Your boiler has failed to ignite, meaning it cannot light the gas to provide heating or hot water, often due to a lack of gas flow or a blocked condensate pipe.

DIY fix possible

Check that your gas meter has credit and that the gas emergency control valve is open.If it is freezing outside, check if the white plastic condensate pipe leading outdoors is frozen and thaw it with warm water.Press and hold the 'R' or Reset button for five seconds to see if the boiler restarts.