FHW Zone is "weak"
I have a 3-zone FHW system in my house, it was a completely new install 7 years ago (formerly steam heat).
The basement zone is acting very "weak" lately, especially when the main floor and second story zones are running. The problem seemed to start last year, when we had a 10'x16' room added to the basement; the contactor tapped into the basement zone, and added one radiator (maybe 10' long). I didn't really notice any problems last year, but I was using a supplimental heater in the bathroom.
This is the symptom:
1) if the two upstairs zones are running, the flow seems to be very little. The first radiator in the TV room gets "warm" but not "hot". The second radiator in the bedroom gets "lukewarm". The last radiator, in the bathroom, does not warm up at all.
2) Once the upstairs ones stabilize, then: the 1st radiator gets "hot", 2nd gets "warm", and the third gets "lukewarm". But it still takes at least an hour for the basement to raise 1F, which is much slower than it used to be.
The zone valve (TACO 570 series) seems to open, but the flow is lousy; I am not sure if it is only opening part way? Also, I am wondering if the addition of the new radiator is causing some sort of line pressure phenomenon or air bubble situation? Hopefully, the contactor did not accidentally block the line by putting a rag or something in there (to stop drips when tapping into the line).
Any ideas are greatly appreciated!
Last edited by WalksInDarkness; 02-29-2008 at 03:07 PM.