Is the thermostat broken on the hot water radiator as it is cold completely in the bathroom the pipes going in are cold. how do I replace it ? its position is top left one nut connection. if I undue the nut will water come out or is it in a casing inside the radiator. ![Roll Eyes :rolleyes: :rolleyes:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)