New boiler

Hayleyjane

Good Morning

Im in need of some help we have just change our old heating system from a cyclinder and hot water tank to a combi and we have a wired thermostat and extension kit to run the old system and it worked fine.

We have move over to a combi and move it to the loft from the kitchen so we moved the extension kit and it all up and running but for some reason the thermostat isn't picking up on the temperature ot the room, the heating is constanly on or it is constanly off. Im not sure where it has gone wrong for it not to work