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pump \"power play'

hr Member Posts: 6,106
is one I purchased to try on a PV powered SDHW. All it ever wanted was a brain, which it recently got! Check out the spec here.


Floyd, I think the key to start up torque is in the DC motors. Suppose you could have 5 zones powered by 5- 7 watt circs. That may get me back from the zone valve world I now embrace :)

ME, it is a 230V 50 hz. Seems to be working fine on 60 cycle. I don't have a lot of info on it, basically the pump and the box it was handed to me in.

I did find a video showing and explaining the Alphas at the GrundfosDenmark site. Along with attractive models in wild clothing?

This version isn't the remote controller version seen at ISH decades ago, but those are shown at the website also.

At this point it looks like Wilo will be first to the US market in UL garb in that 8-10 gpm range.

hot rod

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  • hr
    hr Member Posts: 6,106
    how low can you go?

    I've been tinkering with this Grundfos Alpha circ. This shows it running at a 7 watt consumption while heating a 72" Dianorm panel radiator. My flow meter only reads down to .33 and I am a bit below that line.

    The other radiator is being run with a 15-58 on speed 1, at 60 W. .70 gpm flow.

    I used the infrared camera last week to watch the difference between the panel output at the various flow and power consumptions.

    Of course you will have to attend the Canadian Foothill Conference in Edmonton in April to "see" the difference :)

    Check out Siggy's Feb. 07 column in PM mag for some numbers and thoughts on a 40W circ flowing a 2500 square foot home to comfort.

    Interesting data at the Grundfos UK website regarding power consumption in Europe of these millions of small circs running over there as we speak.

    Time to put those 12 circs, moving 150K systems behind us :)


    hot rod

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  • Floyd_36
    Floyd_36 Member Posts: 2

    I can get the jist of where your going with this and the results of your camera are kind of intuitive from what you posted.
    Now if the pump manufac. would get on board and develop low wattage pumps that had the starting torque,enough head to move water through a reasonable amount of piping, AND had a cost within reason....
    I like pumps, and wish that there was more options.... maybe low watts,torque, and head don't mix????

  • [Deleted User]
    Get ready to forget everything you ever thought you knew...

    about pumping and hydronics...

    The world is about to change DRASTICALLY.

    Think low watt pumps, using only what is required to maintain perfect comfort.

    Think miniature pumps, like one for each radiator or tube circuit, using less than a watt of energy at peak demand. In DC no less so it will be directly compatible with solar without needing an inverter.

    As I explained to the good folks at Wilo, it's going to require us to completely rethink the way we design and install our comfort systems, but it IS worth the effort.

    It is also going to require us as educators to rethink the way we teach about these things.

    Times, they are a changin', and it is GOOD change.

    Imagine being able to take the energy falling on the south side of a room, and transfer it into the north side of the room within a RFH manifold. It's here today. You just have to think outside of the box.

    FWIW, I just roughed in the wiring for my future DCP expansion system in my newly remodeled home/office.

    I'm ready, are YOU :-)

    Tell us more about that Grundfos pump HR. Is it variable speed, constant pressure? DOes it use a ECM motor? Does it require 120V or 220 V? DOes it use pressure transducers?

    Inquiring minds want to know. I remember seeing those pumps at ISH in 99 and being promised that we would see them on this side of the pond in a few years...

    Still waiting.

  • Ted_9
    Ted_9 Member Posts: 1,718
  • Jason Quinn
    Jason Quinn Member Posts: 96
    Alpha Circ's

    Are the alpha circulators available both delta p and delta t? The info and video suggest delta p- if I'm not mistaken- yet HR I believe you have also mentioned delta t pumps also. Does anyone have an idea when they will be available here, if not already available?
  • hr
    hr Member Posts: 6,106
    Grundfos delta T circ have been available

    as the MixuMiser. Basically a 15-42 with a tekmar chip and two sensors.

    hot rod

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  • Jason Quinn
    Jason Quinn Member Posts: 96
    Siggy's 2006 MEC

    Thanks for the response. After I posted my question yesterday, I received my order from Appropriate Designs- the 2006 Modern Engineering Concepts seminar including workbook, seminar CD and Hydronics Know-HOw CD. The first 10 pages answered my question as it covers variable speed pumps-both delta p and delta t. Siggy explains the new technology and like both HR and ME is very excited about its impact on hydronics. I am also going to attend the Grundfos technical training in June at their technical lab-just received the confirmation- thanks for the heads up and recommendation for this HR, I did not know it was even available until you mentioned it in a previous post. This newbie is going to school!
  • 1solarguy
    1solarguy Member Posts: 18
    looks nice...

    I checked out their pv-direct pump on their website. MPPT(maximum power point tracking) built into their pump. that's impressive. I wonder if it's necessary. It sure adds a lot of complexity. I would think it would be a lot less expensive to get a slightly larger pv panel. I didn't see any prices but I bet they're dear.

    I wonder how much better they are than the Ivan Labs El-sid
    pv-direct pumps like the 3watt one on my dhw system.It has done well for 5 years now.A diff thermostat is all that needs.

    However,these look like the way to move btu's from my tarm
    wood boiler into the storage tank in my elecron-challenged offgrid house. thanks,Hot Rod.
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