Welcome! Here are the website rules, as well as some tips for using this forum.
What happens to heating circuit's water during off season ?
Dear Members ,
I have came across a technical problem of a heating system which composes of a non condensing wall mounted boiler ,and poly propylene pipe net work and Aluminum radiators . I examined the system which is as follows :
_ City water as a make - up - cold pressure between 1.5 and 1.6 bar - working pressure at normal operation just for providing domestic hot water for bath and kitchen is 2 bar . PH of heating circuit 8.5 and TDS 70 ppm . Clear water inside of the radiators .
When I got the system checked I found that the heating circuit ( supply and return lines ) did not have shot off valves and the heating system just turned off by its switch . The working pressure was 3.0 bar and there were some drops of water beneath of the wall mounted boiler . As I noticed that there were not valves at heating circuit lines , so I checked the radiators first . When I was trying to pen the bleeding valve of the radiator I heard a noise inside of the radiator which was look like a surge or may hammering .To my surprise , the radiator was full of air and I let the air went out until water appeared out of the bleeding valve . I saw that the rest of radiators were full of air ,and after I took the air out of the whole radiators , the manometer of the boiler showed 2 bar . i checked the make up valve which was closed and it did not let water added into the system . Thus, there are two questions , how the heating circuit water turned into air during off season ,and whether there is chemical phenomenon between aluminum and copper coil of boiler which must be balanced ?
Thank you in advance for taking the time to help me and sharing your invaluable experience with us ,
I look forward to hearing at your convenience time ,