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Pump install, Grundfos alpha 2 26-99F question

Sukhoi29SU
Sukhoi29SU Member Posts: 83
in Radiant Heating
Had a radiant heat system designed. I installed all pex but had the copper, pumps etc installed by a local company.  One of the pumps installed is incorrect.  Design calls for Grundfos Alpha 2 26-99F, and the pump installed was a Grundfos UPS26-99FC.  I have the Alpha 2 on hand now. Question - can these pumps be installed horizontally?  I thought I read somewhere that the pumps need to be installed upright, but don’t understand why that would be.  Figured I’d ask here - I don’t have the manual with me at the moment and can’t find anything online. 

Thanks in advance 

Comments

  • Ironman
    Ironman Member Posts: 7,508
    All wet rotor circulators must be installed with the motor horizontal.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Sukhoi29SU
  • hot_rod
    hot_rod Member Posts: 23,036
    From the installation manual
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Sukhoi29SU
  • Sukhoi29SU
    Sukhoi29SU Member Posts: 83
    Thank you both 
  • Sukhoi29SU
    Sukhoi29SU Member Posts: 83

    https://youtu.be/X4ZvCdhcbBM

    The guy in this video is convinced the problem he’s having with the pump is that it’s horizontally mounted, and says it should be vertically mounted.  I had read somewhere that the bearings go bad under certain install situations but can’t find it. 

  • hot_rod
    hot_rod Member Posts: 23,036
    He is trying his best to give himself bad advise.

    Seems like a lot of circulator for a residential system, the 26-99 is a high head circulator. Luckily he has a hydroSep upstream :)

    The noise in more apt to be some debris in the body or impeller.

    Without adequate air removal, a vertical mount can actually trap air at the check and fail to circulate.

    The directions seem to be clear on acceptable mounting positions.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • GroundUp
    GroundUp Member Posts: 2,064
    What makes you think an Alpha is necessary? Or a 26-99, for that matter? What does the heat load consist of?
  • Sukhoi29SU
    Sukhoi29SU Member Posts: 83
    It’s just what the design called for - I assumed it was needed.


  • hot_rod
    hot_rod Member Posts: 23,036
    Someone that did the tube layout probably calculated the correct circulator 
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Sukhoi29SUGGross
  • GroundUp
    GroundUp Member Posts: 2,064
    Or maybe they didn't. What's the heat load consist of?
    Alan (California Radiant) Forbes
  • Sukhoi29SU
    Sukhoi29SU Member Posts: 83
    edited October 2022
    @GroundUp , designer spec’d 282.2 BTU/(hr ft2).  Project consists of roughly 7500sq ft total, mostly 1/2” pex in concrete , but about 1900 sf of that in sunboard.  Switzer 1750 gal water storage wood gasification boiler will be primary heat source with thermostat that kicks over to FS151 Bosch propane boiler when demand isn’t met with wood burn. The Alpha 2 26-99F is for the two levels of house, and the Alpha 2 15-55F/LC is for the garage with mirrored sf workshop beneath garage. 

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