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Anyone using the Alpha 26-99 yet?

GroundUpGroundUp Posts: 672Member
Hi all, I have a new house and attached garage I bid about a year ago that is finally ready for a boiler now. I laid 9 loops of 1/2" in the basement at 250ft each in a single zone, and 5 loops in the garage split into 2 zones also 250ft long so 14 total. At 30% propylene glycol and .75 GPM per loop, my math says 7 ft of head through the loops and another 10ish through the piping and boiler (UFT-100W piped direct, meeting minimum flow requirements for the boiler with the smallest zone) at 10.5 GPM with all zones calling so I was out of the range of a single 15-58 or Alpha. When I bid it, I was planning on zoning with a pair of 15-58 circs through an SR503 and actuators on the garage manifold to split up the 2 and 3 loop zones. Now that the 26-99 Alpha has come available, I'm considering going that route to simplify things at a pretty modest extra cost. Has anybody played with one yet or have any feedback for me? Possibly a recommendation that I haven't considered? Thanks in advance, you guys are great


  • ZmanZman Posts: 5,334Member
    At first I was excited that Grundfos had finally filed the gaping hole in their Delta P lineup. The controls look pretty limited.
    The alpha 2 15-55 has a top end of ~12ft and 7 gpm in CP3. The alpha 2 26-99 starts at 25ft and 13 gpm on CP1.
    I run into quite a few retro projects that need 12-15ft and 15+ gpm. The Taco VR3452 is still be best choice for those jobs.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • GroundUpGroundUp Posts: 672Member
    Correct me if I'm wrong, but I believe the Alpha will ramp down to a near stop in order to maintain CP or PP so those numbers you listed are the top of the curve. That's what I've seen with the 15-55s at least, when a single loop is open it will maintain a proper flow rate just the same as when 6 loops are open despite what the curve shows on paper. So with that said, my 17 ft of head and 10 GPM hit just about nuts on with PP1 on the 26-99 but the low end is off the chart with only 2 loops open. If it behaves like the 15-55 though, it'll ramp down to 10 watts if it has to and fulfill that need. I may very well be out in left field, but that's what I have observed with the 15-55. Also the Viridian is WAY out of the price range for this particular job
  • ZmanZman Posts: 5,334Member
    I almost always run the 15-55 in cp mode. It would be nice to know if other options are available on the 26-99. I do love the way you can set the Taco to the exact spec you want, yes it is in a whole different price range. To bad the Grundfos folks have never heard of Heating Help. It is so nice to have Taco experts chime in, even when the question is about another product.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Steve Thompson (Taco)Steve Thompson (Taco) Posts: 175Member
    Hey Zman - Joe Matt, Dave H, John B and other folks here at Taco appreciate your kudos big time. The Wall is hugely important to a lot of things we do here (manual updates, product development etc.) - and the feedback from you Wallies is invaluable.
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