this week when we switch off the heating the rads have been staying hot, we tried switching off the hot water too but this didnt work, the thing is the boiler is not firing up as it normally does when we use hot water or the heating, it is as though it is residue hot water, but in the end after 7 hrs we had to switch off the boiler itself, any ideas. Forgot to say it is an outside boiler in a green metal case 2yrs old. also the pressure is on .50 ie half way between 0 and 1. but the pressure is ok for the water etc. and all is working fine with the heating when its switched on, the problem is when we put the heat off the rads stay very hot.