hi all i have a ravenheat rsf 820t combo boiler the problem is the dhw will not auto light the only way i can get hot water is to switch over to ch it then egnights and i run the water (hot water)and then switch off the ch can anyone help i don't know if it is the three way valve or micro swithes !!!!!! any help would be greatly accepted thans steve ![Eek! :eek: :eek:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)