I am new to this place and looking for help. Just feel that I wanna try to fix my heat system by myself rather than waiting for (really sucking) pes&g guys.
Repairmen came days ago and was bleeding the system. Now the radiators on the 2nd floor is warm, but the ones on the 3rd floor are not. I tried to bleed at one of the radiators on 3rd, water came out, it turned warm for a while but again became cold very soon. When I check in the basement, one of the pipes on the top-left corner of the picture is hot, the other is not (as marked in the pic)
That is a brief look at the heating system (boilers and pipes) in the basement. On the top-left corner there are 2 pipes which, I believe, come into 2nd and 3rd floor of my apartment. No other valves are found. The pressure meter is provided because I want to know whether that is too low pressure.
Any idea why this is happening and how I should solve that?