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Primary Pump Viessman KM bus ?

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heathead
heathead Member Posts: 234
in THE MAIN WALL
What is the work around for the US version of the KM bus  primary side pump.  Can one use some adapter with the  KM bus so it provides a output Voltage 0-10 volts to control pump speed. Model is B2hA19. I want to keep all the features of the control that is built into the boiler.  Could one buy the 220 volt European pump and run it at 60 Hz vs 50 Hz at 240 volts of course just wire it with relays that would energize the pump with 240.   I would think that the boiler controlling the speed would be the cream of the crop. Would the extra costs have a ROI  for the expense of the work around required.    Or is one just better to go with the 15-58 and be done. 

Second thought  to just Use the Ecocirc Vario pump and set the speed fixed?  Try to figure out if it would save enough electricity to be worth the upgrade from the Standard to ECM motor.  Thanks as always for the great thoughts. 

Comments

  • icesailor
    icesailor Member Posts: 7,265
    edited March 2014
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    x

  • Paul Pollets
    Paul Pollets Member Posts: 3,656
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    Primary pump on Vitodens

    For the older models (WB2B) the primary pump wires into the Power Pump Control Module and needs to pump 6-17 gpm, depending upon the load attached to the system side of the Low Loss Header. Min. is 6gpm.



    On the new models (B2HA) (with the black control), the primary pump wires into the KM Bus, which has replaced the older Power Pump Control Module. It's still a relay box that mounts on the wall. We always use a Grundfos 15-58 for the primary pump and usually the Alpha pumps for the radiator or RFH load. There would be no advantage to changing the pump voltage as the system is meant to work "as is". The best savings or ROI will come from using "Smart" pumps on the system load.

    You'll also void the warranty if system is not installed per factory wiring diagrams.
  • CMadatMe
    CMadatMe Member Posts: 3,086
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    No

    The variable speed pump options in Coding 2 are shut off for N. America even though the coding addresses are in the manual.

    There was an error rendering this rich post.

  • Gordan
    Gordan Member Posts: 891
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    Don't you just love...

    Don't you just love this de-contenting and dumbing down of products for the American market?
  • SWEI
    SWEI Member Posts: 7,356
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    Definitely

    ...for some definition of love.

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