We recently moved into a 90 year old home. The heating system consists of a hot water system. The first floor has a total of 5 radiators and the second floor has an additional 5. When we moved in, the valves of two of the radiators in the second floor were closed. When we tried to run them by opening the valves, we discovered only part of the radiators heat up, and that a noise resembling flowing water occurs. We tried to bleed them by opening the relief valves, but we have not been able to get water to come out, even after having the relief valve open for a long time. Any suggestions?
Dear Ledarman, .... Just had a similar problem arise at my next door neighbors 120 year old school house he bought last year! We could only get heat through half of some of the basebord radiators... Solution.... Trapped air that was not escaping from bleeder valves due to but not limited to OLD pipes,sediment oxidation,hard water,etc.We ended up reducing system pressure and cleaning/replacing some air bleeding valves as some were corroded badly. Start from point of beginning raditor in that zone until you reach the last radiator in water flow directon. You should get A little watter discharge from a bled bleeder...Hope this helps