I have a problem with my vokera 80sp?

Hi
I have a vokera 80sp combi boiler. The boiler has stopped producing hot water for both the central heating and the taps. The pilot light is lit and when you turn on either the hot water or the central heating the various valves/switches move and the pump kicks in but the boiler doesn't flare up. Is this an easy/cheap fix as I'm currently renovating my first property and want to keep costs down.

Many thanks