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Chilled water coils

for doing dehumidification in an airstream, I am using chilled water coils.



However, I am not finding any that are "ready to go". they all require custom tin work for condensate removal and, since I need a *lot* of exchanger area, to adapt to 6 to 8" round duct sizes.



does anyone know of:



1. ANY chilled water coils that come housed and ready to go?



and



2. If so, any that would adapt with 6 or 8" round adapters that are commonly available? maybe in a couple of steps?



thanks.
Rob Brown
Designer for Rockport Mechanical
in beautiful Rockport Maine.

Comments

  • Charlie from wmass
    Charlie from wmass Member Posts: 4,318
    Unico uses chilled water

    I think their coils will be far larger than 8 " though. Rittling also has fan coil units. http://www.rittling.com/literature/catalogs/Hydronic%20Fan%20Coils_Jan10_web.pdf
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    edited May 2010
    Thanks charlie

    those might come in handy, but I'm looking for duct-mounted units. The fan part is already taken care of, I just need to wring the moisture out.



    Currently I've got an H20 coil unit, but at 24x24 and no housing I have to do a lot of custom work to get it into my ERV ductwork.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • TonyS
    TonyS Member Posts: 849
  • Techman
    Techman Member Posts: 2,144
    ERV?

    What size ERV do you have?And what size ducts are on the ERV? The ERV does not exchange enough of its own energy? How long of an on cycle does the ERV have?Just wondering why you need a dehumidifier in line with the ERV?
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    we're doing radiant cooling

    with what's called a "DOAS" or "Dedicated Outdoor Air System". Basically, we use the radiant panel to handle most of the cooling load, but we have to handle ALL of the dehumidification in the airstream, and the only fan unit we are using is the ERV... no recirc or conventional AC units or dehumidifiers.



    With a properly sized coil and some other design considerations, we can do this in the ERV airstream... the ERV itself just helps us maintain the humidity differential once we have created it.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    thanks tony

    looks like some workable stuff there!
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • Devan
    Devan Member Posts: 138
    Air Handler

    Rob,



    I think your best option is to use an air handler, with duct work sized for the cfm's needed to move air. Tie your water coil into the duct work, with the ERV ducted into that as well.

    8" round won't move a whole lot of air, otherwise you may still end up with moisture issues.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    no way devan!

    I'm taking out all the moisture in one shot, and all air in the building is coming from the ERV. Saves a boatload of unnecessary fan energy and ductwork costs. that's the "DOAS" methodology: the whole point is to do only IAQ ventilation CFMs, and do all the sensible load from the panels.



    http://doas-radiant.psu.edu/



    fun stuff :D
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • Devan
    Devan Member Posts: 138
    I see

    I was just figuring on "rules of thumb" duct sizing.

    You know - 500-600 sq.ft approx one ton per cooling

    350-450 cfm's per cooling ton

    ductulator sizing fpm's for 8" round, coming up short for a whole building.



    So, what methods did you use for determining cooling loads(latent and sensible), how much OA needed, what will control ERV to run near continously?



    Cooled ceilings, definately some neat stuff, a good deal of info and products at this year RPA show, as a matter of fact I had a pretty good conversation with one gentleman from Austria whom I believe is installing ceiling cooling panels at RPA's new place this week in Liverpool, NY as I type.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    many options

    we are going to start with 'off the shelf' stuff first: dehumidistat controlling the coil, thermostat controlling the radiant panel (either floor or ceiling, since we have both, we'll try them both). condensation sensors to shut off the radiant panels.



    The fan will run at regular setting for IAQ purposes (currently high speed, it's a new offgassing shop, but we'll turn it down soon), just like any ERV, with boost switches for bath exhausts as well. so it will run at base speed, and boost on dehumidification calls or bath exhausts. I *might* add a duct mounted dehumidistat to allow the coil to run whenever incoming air needs conditioning, without boosting the ERV too. we'll see how things run. Boost speed on the ERV is 200 CFM... it's a residential size unit, pretty standard, and that's more than enough CFMs for most homes for IAQ. Pressure switch on the ERV ensues positive pressure and no infiltration.



    I have CO2 sensors as well, so I may just leave the fan on low speed continuous and let the co2 sensing provide baseline speed feedback for the fan as well.



    after that though I've got tons and tons of sensors and wiring options (insert maniacal cackling). I'll be running an ENV system and building my own control routines as needed to dial things in or just to learn.



    does it show that I am psyched to get to play like this? i'm happier than a pig in... um... nice, warm mud.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    First Company...

    makes a WHOLE bunch of stand alone FCU's.



    http://www.firstco.com/



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    man

    seems like there are dozens of options if I want a packaged fan coil.



    not much out there for just coils though that are packaged, insulated, and ready to drain. the fan part is already taken care of....



    maybe we need to get good at bending up tin. blech.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    I think it's official

    the exact thing I'm looking for does not exist.



    and no one makes a 24x24 square x 6 to 12" round adapter...



    man, that stinks. knocking tin is no fun.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
  • Devan
    Devan Member Posts: 138
    First Co.

    First Co. have some very good units with water coils.





    Rob, you could buy duct without too much tin knocking involved.
  • eluv8
    eluv8 Member Posts: 174
    Coil Company

    You might give coil company a call.http://www.coilcompany.com/ 
This discussion has been closed.