I have a two year old valiant boiler which has been working up until 2 months ago, I have several radiators that come up to temperature, go down but do not come back up again. I have had the system drained, new values and TRV's fitted but still have the same problem
Heating & Cooling - Goodman
Answers & Comments
Do you hear air in the system? It may need to be purged. Do you have the little coin vents on each radiator? Try bleeding air out. Your circulator may not be working correctly. If it is more than 8 years old, it would be a good idea to replace it. By installing the thermostatic valves, you have added restriction to the system. I would suggest stepping up the pumping capacity of the new circulator. Good luck!