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Grundfos Alpha 2 Wiring

Le John
Le John Member Posts: 211
I want to wire the Alpha 2 to a Taco Zone Valve controller and since the alpha's display is always on what is the recommended method to wire it to the Zone Valve controller?

Comments

  • Zman
    Zman Member Posts: 7,434
    If you turn off the pump, the auto adapt feature will reset each time. What you are suggesting will work just fine in the constant pressure or fixed speed modes. Just cut the cord end off and wire it to the controller.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
    Solid_Fuel_ManSuperTech
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,542
    I too like to see everything turn off when not in use!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Big Ed_4
    Big Ed_4 Member Posts: 2,065
    I thought the Alpha had a memory
    I have enough experience to know , that I dont know it all
    SuperJSuperTech
  • Le John
    Le John Member Posts: 211
    On the ZVC 404 isn't the power to the circulator interrupted when there is no call for heat? How would the display illuminate when there is no call for heat?
  • SuperTech
    SuperTech Member Posts: 1,854
    You can leave the Alpha 2 powered up all the time, that's why they have the version with the line cord that you can plug in. The Alpha 2 will slow down and stop as the zone valves close. I use it like this on my boiler. The Alpha 2 does have memory as well for on and off applications. I have used it like that as well.
  • Le John
    Le John Member Posts: 211
    thank you @SuperTech - I can add an outlet for the pumps line cord but how will that get wired to the ZVC404?
  • Zman
    Zman Member Posts: 7,434
    If you want it on all the time, you don't need it connected to the ZVC. The alpha will detect when a zone opens and start pumping.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
    SuperTechLe John
  • SuperTech
    SuperTech Member Posts: 1,854
    That's pretty much it. It's designed to be plugged in, left on auto adapt and forgotten about. For people like me they built in constant speed and constant pressure modes to play with 😀. It's a nice pump but I believe it still has room for improvement.
    Le John
  • Dave H_2
    Dave H_2 Member Posts: 519
    If everything is off and not calling for heat, why would you need to see the display? The most efficient circulator is the one that is off.
    Cut the plug off, strip back and wire it to the ZVC.

    Dave H.
    Dave H
    ZmanSolid_Fuel_ManKewlwhip
  • Grallert
    Grallert Member Posts: 540
    I've done it both ways, cut the cord and wire to a control of some kind or simply plug it into an outlet. If you wire it to a control it will wake up to a brand new system every time it's powered and have to relearn that system over and over again. If 6you simply plug it into an out let it will power down when there is no call and retain its adaptive memory. It really should have a constant power supply. With all the zones closed you'll see that it's using no or very little power and moving no water the way it was designed.
    Le John
  • Dave H_2
    Dave H_2 Member Posts: 519
    If its being used in a zone valve application, it shouldnt be in the autoadapt mode, it should be in the constant pressure mode so there is nothing to learn.
    the autoadapt mode should be used with thermostatic radiator valves.
    So powering down after use will not affect the performance of the circ.
    5 watts is still 5 watts.

    Dave H.
    Dave H
    Le John
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,542
    I agree, I dont like the deltaP pumps running at a minimum speed just waiting for a valve to open. I'd rather power it down.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Le John
    Le John Member Posts: 211
    edited March 2019

    I agree, I dont like the deltaP pumps running at a minimum speed just waiting for a valve to open. I'd rather power it down.

    @Solid_Fuel_Man if using the plug - does that mean the pump is always running even though the zone values are closed? With all zone values closed is it actually moving any water?
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,542
    Yes, it is spinning. Not moving any water, its keeping the differential pressure to "see" when a valve opens. Otherwise it's just a pump upstream of some valves.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • hot_rod
    hot_rod Member Posts: 18,195
    Another option was to wire it through a Caleffi relay which will exercise the circulator occasionally throughout the "off" season.

    Possibly some of the boilers also have that exercise function built into their on board controls?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • SuperTech
    SuperTech Member Posts: 1,854
    The Honeywell L7224U has pump cycling built in, as does many condensing gas boilers
  • Le John
    Le John Member Posts: 211
    Doesn’t the Taco ZVC have this built in to the control? It is wired to a Lochinvar Noble Combi.
  • hot_rod
    hot_rod Member Posts: 18,195
    Le John said:

    Doesn’t the Taco ZVC have this built in to the control? It is wired to a Lochinvar Noble Combi.

    Usually there will be a DIP switch on the board to enable an exercise function. Here are DIP switch options on the Caleffi ZVR, it varies from brand to brand, as to the features and functions..
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,542
    Shouldn't let the pumps "rub" for 30 seconds after 72 hours of non operation😁 think I found a typo hot rod.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!