Hi, first post but have a problem so hope someone can help. Recently moved into a new house. Heating system originally had no room thermostat. The wiring was still in place for one, it was just set as if there was a constant call/demand. The previous owner explained that the system did still have something in place to prevent the boiler from just contiuously cycling and that he controlled room temperatures via TRVs on radiators. Having queried this, a room thermostat was re-installed. Since then, I've had some issues with boiler responding to room thermostat. Thermostat clicks but boiler shows no demand. Eventually,it reacts somtimes after 5 mins sometimes longer. Then boiler went off completely, discovered it was a blown fuse,so replaced the fuse. Boiler is now 'working' again. However, the problem is that it won't stop working. I had set the heating controls to come on at a certain time and then go off at a certain time. When the time came for it to turn off,it just kept going. The light on the timer clock has gone out, showing the timer is not demanding any action, but the boiler just keeps firing. Can anyone provide any advice as to why the boiler would keep thinking there is demand (the demand light on the boiler keeps flashing), when the timer controls are set to off (both heating and hot water are set to off). One thing I did notice is that if I cycle through the hot water options on the timer (i.e. on/timed/once/off), the boiler demand switches off when the hot water goes past off, but then it comes back on again after a while. Any advice is geatly appreciated.