OP
keiron12
As I said before you dont need to disconnect the thermostat(s) just turn them all down this will highlight what what ones are working also if there is 4 stats and 4 rooms they should all be wired the same so check this out as well because if on room is wired to the NC contact intead of the NO the the stat will work in reverse ie turn it down to 10 degrees and the heating stays on
You may be on to something here - reason I removed the thermostat is because I had turned the temp down, but the floor was still warm the net day. What do you mean by 'wired to the NC contact instead of the NO'?
Here's a pic of the thermostat:
http://dl.dropbox.com/u/1253640/photo.JPG