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Close-coupled in-line circulator mounting positions

RPKRPK Posts: 82Member
edited July 31 in THE MAIN WALL
Is this an acceptable orientation for this pump? 3HP, Armstrong Series 4380. I’m not used to seeing circulators this large mounted this way. The installation manual says these pumps (up to 15HP) can be mounted with shaft horizontal, but only shows a picture of a pump installed on vertical pipe. I accidentally posted the wrong picture last night... here’s the one I meant to post.


  • RPKRPK Posts: 82Member
    I accidentally posted the wrong picture last night (of a pump mounted with vertical shaft). The correct picture is there now.
  • hot_rodhot_rod Posts: 12,042Member
    Some installers prefer the wiring terminal box on the top
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,760Member
    I would clock the motor 180 degrees so the wiring is on top. I know Taco specifically forbids the box at the 6:00 position like that, I'm sure others do as well.
    Serving Northern Maine HVAC, and Controls
  • RPKRPK Posts: 82Member
    What is the reasoning behind keeping the box on top? Just to minimize chances of the box getting wet in case of a leak?
  • ScottSecorScottSecor Posts: 330Member
    This pump appears to be a "vertical" type pump. Not sure why one would specify or design a system with vertical pumps, only to be installed horizontally? On the jobs that we installed or serviced vertical inline pumps they were typically tight on space and these pumps took up less horizontal space (especially compared to base mounted pumps). One of the reasons I am not a fan of these vertical pumps is they almost always require a ladder to service them. Another common problem with the larger versions (say 10 or 15 hp), we try to use rigging to raise and lower the pumps/motors only to find that we cannot get an extension ladder in between the pipes or duct-work to get to the steel framing above the pumps.

    In this particular case, I suspect the designer did not plan on having what appears to be duct-work right on top of this pump. I'm thinking the pump installer was forced to mount the motor/veloute sideways due to the tight clearance.
  • SteveSanSteveSan Posts: 35Member
    Taco does suggest if a Taco Vertical In-line pump like our KV series you can mount horizontal. Here is the link for our IOM on KV series. But to be on the safe side I would contact Armstrong for their advice. Also you never want the motor box at 6 o'clock in case of water or condensation getting inside the the motor box.
  • SteveSanSteveSan Posts: 35Member
    That is up to 15HP motor.
  • RPKRPK Posts: 82Member
    ScottSecor, yes I believe this was due to an issue with clearance between the motor and ductwork above. There are many more in-line pumps of this style on the job and this is the only one mounted in this fashion.

    SteveSan, good point about condensation, especially in this case as this pump is on chiller water.

    Thank you everyone for the comments.
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