boiling

Hi! Following some ongoing problems my Boiler Thermostat has completely stopped working rendering my heating non existent! The overheat reset button is now not working at all. I also believe that the actual thermostat function has stopped working properly - for some time have been having...

I moved into a 1980's house a few weeks ago. The house has a Ideal Heat 30 boiler in kitchen with cylinder in airing cupboard and tanks in loft. Under boiler there are 3 motorized valves, 2 for heating and 1 for HW. The 2 heating valves are wired together into stat (as there arent seperate zones...