volkera linea 28 no hot water?

There is no hot water coming from the combi boiler, I ve re presurised, possibly too high as it now reads 2 bar,there s no pilot light and a constant rattling like noise heard i ve tried the 10 second re set.The electrics are fine, it s as if there is no gas going into the boiler.....can any one help please? 2 kids and one wife with no hot water is no fun...