big loop , it will not get hot

dana_3

just change out the secondary circ. to a 0010 taco. the 007 is too small for run

angel fernandez-homeowner

problem loop

i've install a Pearles Pinnacle at my sons house, with a hot water parner. there are four zones, basement, first floor, second floor, and hot water. All the zones draw heat fast but the second floor takes forever. What can I do. the zone is about 160 feet, all with 3/4 " pipe. thank you in aveance for you fine service.

[Deleted User]

you can turn it into a split loop and put in some balancing valves. should help the problem

Brad White_123

A few questions for you-

1) Are the zones operated each by their own circulators or zone valves?

2) If zone valves, does the heating problem occur when the other zones are calling? (That may be solved by balancing valves as oilguy suggested -adding resistance to- the other zones which heat faster; call it "sharing the love"
Splitting the zone may also help as oilguy suggested. It should cut the pressure drop by 75 percent if you cut the flow to the zone equally in half.

3) How does this zone circuit compare to the others? Are the other zones significantly shorter and less "fitting intensive"?

4) Is the zone completely air-free? Any pockets of air that may block flow? Gurgling? Can the zone be purged and high points vented?

5) Do you have a heat loss calculated for the zone? (The house overall but this zone in particular?) If not calculated, do you have a "gut check" comparison of how this zone compares to the others in terms of windows, wall areas and volume served? And how does this compare to the amount of radiation serving that zone? If short on radiation it certainly will take longer to heat.


If you are using circulators and the 160 linear feet is correct, that does seem at first "a little high" in terms of resistance but can be easily overcome especially if you are using circulators. Say that zone has enough elbows and offsets to make the equivalent linear feet double that- 320 feet.

At a generous 3.0 GPM and 20 degree drop in water temperature, that is 30,000 BTU's per hour. That would heat about 750 SF of reasonably insulated older construction as a point of reference only (40 BTUH per SF at design). That might also correspond to 60 feet of baseboard fin-tube at 500 BTUH per foot. Again, point of reference only.

That pipe circuit would also would impose a pressure drop rate of 2.49 feet per 100 feet of pipe (Type M copper assumed), almost 8.0 feet of head. A Grundfos 15-58 on low speed would deliver that with ease.

Some thoughts to work with anyway-

Best,

Brad

angel fernandez-homeowner

big loop-it willnot get hot

#1 zone valves, #2the walls are closed & finnish, #3other loops are mucu shorter, no problem there.,#4 followed Dan's advice of pumping away(I purchased the book PUMPING AWAY) , and vented the zones and it work perfect.
Question. Could I add a Circulator to that zone, on the return side. Since the walls are finnish, it would be a lot or trouble to do the split loop.
Again thank you for all your help.

Brad White_9

My choice would be

to add a circulator to the problem zone if you can, on the supply side (yes, pumping away). This way you will be spending that electrical power only for that zone rather than pumping the entire house for the sake of that zone. That is one way to do it.

Absent that, you could also cut in balancing valves on the shorter zones (Macon Controls or Tour and Andersson make nice ones, very smooth and linear). Throttle down the "easy" zones until you get sufficient flow in your problem zone. If that does not work you may need a more powerful circulator, which brings me back to my first choice.

Splitting the loop is a nice thing to do but not essential. Sometimes you just have to admit defeat...

Congratulations on buying Pumping Away.

Brad

Jerry_15

cut off the other zones and see if you can blow it through with the pump. You got an air lock. balance it after you get flow. Good luck. Sorry to be so simple; let me know how it works out.

angel fernandez-homeowner

hard to heat aone

I have already ran that loop alone, and after 2.30 hrs , the two rooms at the end of the loop, are still cold. IF I install a pump on this loop, how do I wire it , remember I have 4 zone valves, a primary pump (taco 012, and the second pumptaco007 ), I had to do a primary & secondary loop as recomended by the peerles rep. this boiler needs to run 12 gls/mt for it to be eficient.

THANK YOU ALL FOR THE EFFORT IN HELLPING ME, THNK YOU.

Weezbo

bite the bullet and split the loops.

find what may be somewhat an arbitrary mid point run pex back through the convector covers until you see something that looks like a closet and drop the two pipes back to your header.