how do i fix my baxi 80eco combination boiler?

boiler firing and giving hot water ok. When put heating on not firing. When switch is selected for heat and water boiler will stay running when the hot tap opened first and then closed. I think it has something to do with divester valve as i can see a solanoid come out and make the switch when tap opened. Also the glass in the pilot window has shattered and their is no explanation from me! The boiler has not been attacked! Did notice that when it fires their is quite a big bang from chamber. Could this be why? Should i do a burner pressure check?
Any help appreciated.