System/Pump curve for replacement

2468ben

Hi all,

I've got fin-tube with 4 zones on zone valves, and an old circulator I'd like to replace with a delta P pretty soon. Thanks to Idronics and a long weekend, I went around the pipes and got some pretty math-on system curves depending on which/how many zones are open. I only guessed a little on the curve for all 4 zones at once, because the shared pipings overlap in too many different combinations.

I also found the pump curve for my 15-58 running good enough on medium, and the curves for the Alpha2. But my load is only 50kBTU on a design day with no sun, and the zones would be about 10, 10, 10, and 20.

So which of those delta P settings would cover my bases? I spent so much brain on figuring out the curves, I can't tell if the flow would be too low running a single zone or too high running all of them.

hot_rod

Do you have the Alpha 2 already? Maybe look at the Alpha 15-58, they made tweaks to the autoAdapt function and you have either that or constant pressure mode for zone valves.

A tad bit more performance, the second number in Grundfos speak is the head. Alpha 2 is 55, Alpha 15-58 is 58dM.

You can watch, data log, and adjust the pump with the GO ap, also.

https://video.search.yahoo.com/yhs/search?fr=yhs-ima-st_mig&ei=UTF-8&hsimp=yhs-st_mig&hspart=ima&p=grundfos+GO+ap&type=q3000_A1BWP_set_bcrq#id=1&vid=7db11ca4a60c1fff87fcaa044943d5d1&action=click


file:///Users/bobrohr/Downloads/Grundfosliterature-6859663-ALPHA-15-58-IO%20(4).pdf

2468ben

Thanks, didn't buy one yet, I think I got confused by some mislabeled products on a supply site and didn't realize the alpha 15-58 isn't an old version of an alpha 2.

The alpha 15-58 constant pressures are 6/10/15 instead of the 6/9/12 I had above. Would 6 or 10 be a good match for my system curves?

And thank you for all posts + resources you've made to get me this far already!

hot_rod

2468ben said:

Thanks, didn't buy one yet, I think I got confused by some mislabeled products on a supply site and didn't realize the alpha 15-58 isn't an old version of an alpha 2.

The alpha 15-58 constant pressures are 6/10/15 instead of the 6/9/12 I had above. Would 6 or 10 be a good match for my system curves?

And thank you for all posts + resources you've made to get me this far already!

I would start with the AutoAdapt function, it may be smarter than we are finding the sweet spot. It takes days for it to learn all the systems varying hydraulics as zones open and close.

It is a bit confusing as there is a lower featured 15-58E, in addition to the Alpha 15-58