Maybe one of you guys can help me out. I’m having a hell of a time getting the air out of my baseboards after changing out one of the circulator pumps. Mind you I’ve done this before, but I just can’t seem to get it. The attached diagram is the typical setup I have; only I have 5 zones, so what you see plus 3 more. Maybe I’m not bleeding enough water through the zones or my procedure is wrong but I just can’t seem to get the air out.
My basic procedure is to isolate all the zones (closing supply and return side isolation valves) than open the supply side isolation valve and check/flow value for the zone I want to bleed. Then I open the fill valve and have at it. The first question is how much water would it take to bleed the zone if the zone was about 25ft vertical from the boiler? Or how much run time? Either will suffice as I’m thinking I’m just not doing it long enough. . .
Secondly is the procedure correct?
TIA.
www.josephfusco.org
http://joes-stuff1960.blogspot.com/
Edited 2/21/2008 5:05 pm ET by Joe
Replies
The best way is to use bleeder valves on the high points of the system.
http://www.palmer-pursuit.com/cart/index.php?main_page=product_info&cPath=21&products_id=115
Problem with trying to force air out on the low part of the system is that circ pumps don't usually have a high enough flow rate to force the air down.
“The world is a dangerous place, not because of those who do evil, but because of those who look on and do nothing.” —Albert Einstein
Are you saying that you use the boiler fill valve to flush the loop? From what I understand you will probably need to fill with a hose . The boiler fill often doesn't flow fast enough to clear the pipes.
Yes I am. I've done this before with prefect results and I'm thinking that it's the onset of Alzheimer's or something.Regardless of the fill, is the procedure correct? With that in mind how many gallons do you think it would take the flush the upper zone? Like I said, I think I'm remembering it took less time when it may have taken longer. http://www.josephfusco.org
http://joes-stuff1960.blogspot.com/
Edited 2/21/2008 3:27 pm ET by Joe
25 foot height, times 2, is 50 feet of run. Assuming 3/4" copper (assume id of .375"), and 7.4 gallons per ft3, the 50 foot length to fill would be about 1.25 gallons.
Length, times area of pipe, times 1/144 conversion factor, times 7.4 = 1.135.
I've swept unvented baseboards out in the past, but not usually at that height.
Given the 25' rise, you're gonna need at least 11 psi just to reach the top. My own house has an attic heater, and I crank my psi up to about 20, but then I've installed bleeders up there to vent it.
Good luck.
"I am the master of my fate, I am the captain of my soul." Invictus, by Henley.
Nick,Dick,The boiler runs at about 22psi and there is a lot more piping on the floor. The reason I asked about the water was that I ran about seven 5 gal pales through.So what about the procedure?BTW thanks for the replies. . . .http://www.josephfusco.org
http://joes-stuff1960.blogspot.com/
Joe, hopefully you got it by now. If not, like Dick said, hose and full blast. Shouldn't take that much volume to clear the line. Remember never let the cold water shock a hot boiler, could crack it.
Rich
This has come up before. Try a search here to locate the various pieces of advice.
My system has a return shutoff, with boiler drain valve just upstream of it, near the boiler, for each of about six loops (on 3 circulators). There is a bypass valve around the pressure regulator valve.
What I do is, one loop at a time, close off the return, attach a piece of hose (old washing machine hose does it) to the boiler drain valve in the line and run it to a large bucket. Then I open the boiler drain valve and the pressure regulator bypass to force water through the loop.
The flow is full blast. Hold onto the hose, because when the slug of air comes down the pipe the recoil can send the end of the hose out of the bucket.
The tiny vent valves at the (hopefully) high points in the loops can be used to vent most of the air for initial filling, but I find that there always is a bit of air lurking in the pipe at the end. Also, if the horizontal runs aren't perfectly level or sloped up toward the vents, you need a blast of water to rocket the air out of there.
I'm with Dick; hook up a garden hose to the boiler drain, with all other valves closed. Open the supply valve for the zone needing to be filled, and throttle open the supply to the garden hose. Watch your pressure; your relief might lift. They should be set around 30# or so.
Ideally, you should have vents at the BBH, or a hose connection on the supply side inside the zone so you can drain/fill the zone independently of the rest of the system..
Once upon a time, to replace the circulator, I had to dump my heating system fluid on the basement floor (it has antifreeze in it.) Since then, I piped up a fluid storage and transfer system so I can move the fluid whenever I want, without spilling a drop. The tank is an unused polyethelene gas tank for a boat. Lots of controls and indications. Looks like the power plant I used to work at.
"I am the master of my fate, I am the captain of my soul." Invictus, by Henley.