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residential chillers anyone?

I have an upcoming project I'm considering using Hi-velocity system with a chiller.

Because chillers are rare in residential settings, I'm looking for any info, piping , pump sizing, etc.

Background info on home is slab on grade, no attic space either, very well insulated (double 2x6 walls) radiant heat in slab ( but may not option for radiant cooling) however chill piping integrated into primary loop from boiler piping.

Guest house (25x25) connected via courtyard to main house (25x75) outdoor chiller on far side of guest house, 2 ton SpacePak for zoned guest house, 3 ton zoned for main house, 5 ton chiller 120' CWS and CWR piping each way.

Split ductless units was ruled out btw.

Thanks in advanced!


  • Tom Blackwell_2
    Tom Blackwell_2 Member Posts: 126
    Normal ranges

    Chilled water is typically at 42-45 degrees and coil temperature rise is usually 10 degrees, although more delta-t is better-results in less pumping horsepower. Chilled water circuit would be a closed system with bladder type expansion tank and standard make-up. If applied in cold climate, may need glycol for freeze protection. Must have some means to keep the chiller happy at light loads and a way to maintain flow through the chiller. The best option is a storage tank with both chiller pump and secondary loop pump, but if cost is excessive you can get away with using all 3-way coil valves or let the coils run wild and use fan control. Piping velocity should not exceed 3 feet per second for noise reasons, otherwise you can go to a max of 10 fps if noise is not a concern. If humidity control is important select at least 2-row coils, 4-row if possible-this will also mazimize the delta-t. Let us know what you come up with.
  • Devan
    Devan Member Posts: 138

    I found some good info on UnicoRC chillers at their site.
  • MarkPFalade
    MarkPFalade Member Posts: 68
    edited September 2009

    They make gas fired chillers. Nice units, I couple one to some unico air handlers and radiant floors and it works quite well.

    [url=http://www.robur.com/us/]http://www.robur.com/us/ (I think)
  • eluv8
    eluv8 Member Posts: 174

    Multiaqua used to supply Unico their Unichiller until Unico decided to make their own. Multiaqua still sells chillers under their own name from 3 to 10 ton 1 and 3 phase, including a 5 ton reverse cycle. We have had good sucess with them on several larger homes.
  • Tranberg
    Tranberg Member Posts: 4
    Modulating chiller

    Acson/McQuay make reverse cycle chillers that use inverter-driven compressors well known from ductless split A/C systems.

    If I lived in a climate where residential A/C was a must-have, I would install a modulating chiller in my house.
This discussion has been closed.