What size and type of OWB pump?

[dean06919]

My OWB sits between my garage and house. It is approximately 90' away from my house and 70' away from my garage and has one 1.5" inlet and one 1.5" outlet. Can I use one large pump and T off of it to hook up my 1 inch pex lines from the house and garage? If so, what model number pump should I use? Or, should I use a 1.5" x 1" x 1" or 1.5" x .75" x .75" T on my inlet/outlet to run two pumps?

Thanks for any input. I have a two week break coming up and want to have all parts on hand to complete this project in one day.

 

[rx7145]

My OWB sits between my garage and house. It is approximately 90' away from my house and 70' away from my garage and has one 1.5" inlet and one 1.5" outlet. Can I use one large pump and T off of it to hook up my 1 inch pex lines from the house and garage? If so, what model number pump should I use? Or, should I use a 1.5" x 1" x 1" or 1.5" x .75" x .75" T on my inlet/outlet to run two pumps?

Thanks for any input. I have a two week break coming up and want to have all parts on hand to complete this project in one day.

I would run two pumps. If you run just one the water will flow the loop with the least restriction in it. Then the other loop will not get any flow. You "could" balence them out with a haft closed ball valve but I don't see that as being the right/ best way.

I would use a 1.5x1.5x1.5 tee with two B&G PL-30 or NFR-36 pumps.

http://www.bellgossett.com/literature/files/1083.pdf
http://www.bellgossett.com/productPages/NRFcurves.jpg

 

[projectsho89]

Actually, you won't get all flow through one and none through the other if you run a single pump.

Without any balancing, the loops will each flow an volume that is directly proportional to the relative resistances (head) of each loop. If the pump has enough mojo, a simple ball valve on each loop will allow you to balance the flows. You'll have to figure out your head so you can properly size your pump requirements.

Steve

 

[Slick]

Not to jump in but it might help the original poster as well...but how do we calculate head? I'm doing this for my owb install right now...my second pump (to my house) has to go up almost 14 feet then across an ibeam then down 14 feet then level a bit over 100 feet to my house....so that's 14 feet up on the way there and on the way back...does that make it 28 feet head or does the fact that it comes back down 14 feet help pull it like a siphion and reduce it? My dealer said a taco 13 (which I see has up to 32 feet head)but he just kind of did it in his head so figured I'd ask around before dropping the $$..pumps with this much head aren't cheap....

Along the same lines...how many gpm do we need out of an owb? I noticed as head increases gpm decreases. I'm doing baseboard radiators if it matters....

Again sorry to jump in but if your shopping for pumps, you'll need this info also

 

[dean06919]

Again sorry to jump in but if your shopping for pumps, you'll need this info also

Great question Slick, thanks for jumping in. I'd rather do it right the first time.

 

[rx7145]

Here is a good link that donsalo posted: http://www.aquariumpros.com/articles/headpress.shtml

 

[Slick]

Finally got through to Taco tech support...wouldn't help me pick a pump until I knew my flow and head....hmmm, that's what I wanted to discuss...he forwarded me to this http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf which I haven't picked through yet but he did say a quick way to calculate head is total linear feet of travel x .06 but the formulas in the pdf are more accurate...he also blew holes in what everyone else has been telling me about needing a high head pump because I'm pumping water up over my shop...he said the water is already up there there so your not pumping it up as much as pushing some of it to fall back down the other side...guess the siphion analogy I was picturing is true...might save me some serious coin on a pump. gotta go read that pdf....

 

[mtfallsmikey]

Also translates into 6' of head /100 ft. pipe. Head pressure not necessesarily all about vertical lift, it's about total resistance of pipe/fittings.