Just wondered if anyone had experienced anything like this before I call Glow Worm on tuesday. Have just fitted new Ultracom 18 sxi system boiler to an existing system. System is Y plan and have also fitted new Honeywell 7 day programmer and roomstat - although this problem is not related to external controls. Calling for heat or hot water or both and everything works fine however if HW and CH are switched off at programmer the boiler still stays running. Putting a meter on the switched live at the boiler shows no voltage so the controls arent calling. I have even removed the switched live wire from the boiler so that it just has the power supply, switched the boiler back on and after a few minutes it will fire up and stay burning at a low rate. the boiler is inside the house and there is no frost stat wired up.??
Many thanks
Many thanks