I have a tankless boiler that's used for both heat and hot water. We bought the house in the summer and since the hot water worked, we just assumed the heat would too. We turned on the thermostat for the first time and nothing happened. We still have plenty of hot water and have hear the boiling running to heat the water, but no matter what we do with the thermostat, we get no heat at all. Please help.
Without looking at your system the first thing that comes to mind is the motorised valve sticking. This is normally close to the boiler and it is inside a galvanised metal box on the pipe work. If you find it there is a lever at one end that you will be able to pull across to help try to release the valve. This valve runs in conjunction with your programmer to put water to which ever system is calling for heat. If the valve is found to be faulty you do not have to replace the whole valve. There is replaceable electric motor inside box that can be easily replaced. Cost ?10. Hope this is the answer. Should you get it going remember in future to kick in the system once a month during the summer.
give the circulater a good hard tap with the handle of a hammer, this usually works . the circulater has been laying idle for a while and might just need some gentile persuasion to free it up.
