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Community and Q&A

Anyone have experience with Chilltrix equipment?

CARL SEVILLE | Posted in Green Products and Materials on

A client has asked me to evaluation Chilltrix HVAC systems:

It appears to be an inverter driven mini split style system that uses a chiller rather than a condenser. I am assuming that it uses and expels significant amounts of water as it does not use a refrigerant, but their documentation is not very specific.

Any feedback would be appreciated.

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  1. Reid Baldwin | | #1

    I would love to see some third party testing of this product. I am always skeptical when a company that I haven't heard of advertises performance that is a big step above mainstream products. If the product performs the way the website claims, this thing is a game changer.

  2. Expert Member
    CARL SEVILLE | | #2

    Thanks for the feedback. I tend to agree Reid - I am wary of manufacturer's claims that aren't backed up by outside certification. They're claims of AHRI "equivalent" efficiencies is a bit suspect to me. Other than not using refrigerant, I don't see the benefit over standard VRF technology available from Mitsubishi and others.

  3. Reid Baldwin | | #3

    It does seem like you could use a greater number of heads with the same total capacity relative to Mitsubishi or Fujitsu mini-splits. As mentioned in another thread, that addresses a heat distribution concern. That part I believe. You could also mix radiant and point-source forced air which might be valuable. I would like to believe the COP numbers.

  4. GBA Editor
    Martin Holladay | | #4

    You wrote, "This is a water-to-air heat pump," and then you compared it to the Altherma.

    I'm guessing that you meant to write that this is an air-to-water heat pump.

  5. charlie_sullivan | | #5

    This is an [edit air to water] heat pump. It uses a closed hydronic system to deliver heat or cooling to the house but does not consume water in operation.

    It is similar to the Altherma system by Daikin, which is generally considered a good system, but expensive by the time you are done with the plumbing as well as buying the expensive unit.

    However, this thing has amazingly high COP if you believe the plots on this page:

    For example, at -2 C outside (28 F), putting out 113 F (45 C) water, Altherma gets a COP of 2.4~2.45 depending on the model. This says the COP is 4.1! That means it only uses 60% of the energy the Altherma would use for the same conditions, and is on par with ground source heat pumps.

    I'd say this kills ground-source heat pumps, except that most people would say they are already dead, and if they were to use the same level of engineering in a ground-source system, they'd get even higher COP.

    It also looks like they have integrated the pump and controls, which is a good thing for installation cost and likelihood of getting the system working well, without excessive power consumption from pumps, valves, etc. You'll still need to make sure the plumber installing it understands the need to have sealed insulation on chilled water pipes to prevent severe condensation.

    Another good think is that because it's a packaged system, the likelihood of a refrigerant leak is lower, and the quantity of refrigerant is lower, compared to a split system. That's important from the point of view of avoid their severe greenhouse gas emissions.

    And the cost looks quite reasonable: $3400

  6. charlie_sullivan | | #6

    Thanks Martin. Corrected.

    My summary is that performance is very similar to minisplits. It would be nice to have verification of that, but the decision between them would likely based on other factors:

    1. Less refrigerant and less leak potential.
    2. Ability to install without a refrigeration tech.
    3. Ability to use a larger number of smaller emitters to solve real or imagined heat distribution issues, which is useful even if though I suspect the problems are mostly in the latter category.
    4. For heating, the potential to use indoor emitters that are truly silent, either throughout or selectively.
    5. Potential to supply radiant floors for:
    a. Retrofit of buildings that already have them
    b. Owners who are irrationally fixated on them.
    c. Owners who want the combination of silence and invisibility that they provide, while understanding that many of the supposed benefits are hype.

  7. ges74 | | #7

    If it helps at all, I spoke with John at ChilTrix/Hotspot and he explained (to a layperson, mind you) that:

    - Wilco, their parent company, manufactures equipment for various brand name companies.
    - The system is an amalgamation of "best-in-class" components. For example, compressor is Toshiba, valves Demersen? (couldn't catch name), electronics are from Japan, heat exchanger is from Sweden, and variable speed pump is from Germany.
    - Every part is "off the shelf" so servicing should not be difficult. Neither installation nor servicing requires any special certification but experience with chillers would be a plus.
    - 700 units have been deployed in Europe over the past 3 years but when I asked him under what name so I could do more research, he demurred

  8. ges74 | | #8

    He also mentioned that because it uses low pressure water instead of high pressure refrigerant, the pump uses a lot less wattage than competing systems (much easier to push water thru pipes): 22W for ChilTrix vs 130W for MultiAqua.

  9. charlie_sullivan | | #9

    On that last point, I think he was a little confused--the Multi-Aqua is pumping water around at similar pressures to the Chiltrix, but it might be using a low-efficiency induction motor pump instead of a high-efficiency ECM motor pump. And given that the pump is variable speed, nailing it down to one number, 22 W, is a little suspect, but I still expect there's a real and substantial advantage in pumping energy.

  10. zapp1972 | | #10

    We have just had a Chiltrix system installed by America Portable Solar in Cummings, GA. The system performs better than expected heating a 1858 solid brick home with 12 1/2 foot ceilings. There were a few learnings as this is basically a hydronic system. Skill sets needed are much more in line with radiant heat systems that are common in the northeast.
    Units are very quiet and really produce a significant amount of hear for their size. Easiest way to describe them is old fashioned radiators built in the 21st century. Benefit of nice warm heat and ability to cool in the summer.
    Installed one system for each side of the house and will be adding another to a new addition. Recommend American Portal Solar as a resource since they have the skill set and experience to make these system operate.
    We had them also install a 5 KW solar array to offset the increased electrical demand and qualify for tax credits. Both systems are operating fantastically.

  11. user-63068 | | #11

    Jefrey Eastman - did you use the fan coils advertised on the americanportablesolar website with the cx30, or did you use radiant/no-fan hydronic radiators inside the house? Thanks.

  12. rhl_ | | #12

    It’s been a few years now, I wonder if those who have installed chilltrix are still happy with it?

    1. polyakov | | #14

      I installed Chiltrix last year in my house in New York. I am using it for radiant floors in the winter and AC fan coils in the summer. You need to research somewhat about building hydronic systems in general but the company is quite helpful as well with customer support.
      Am I happy with it? Yes. Also, I plan to get solar power to help offset the electric bill which is pretty reasonable considering I heat the house and water tank.

  13. GBA Editor
    Martin Holladay | | #13

    This Q&A thread dates back to 2015. I wrote an article on the topic in 2016 called "Air-to-Water Heat Pumps."

  14. CA_GREEN | | #15

    Hello There,
    I have purchase a home last year with Chiltrix CX30 tied in with Furnace-. The old owner had it installed around 8 months when we moved in. 2 days after we moved in it stopped working with P5 error (blowing only hot air) It was under one year warranty so the Installer came back and tried to troubles shoot.

    I noticed that this guy is not really familiar with this system.
    It took him 2 days to come up with Flow switch issue. He replaced the flow switch and finally it was fixed (Sept 2018).

    Now currently (6-20-2019 )- the P5 error came back again. So I called and waiting for the Technician to come back.

    Not sure If I got a lemon this is new system (less than 2 years old) ....maybe it was not installed correctly...

    More to come... Ray

  15. Doctor_Sally | | #16

    Did you end up using the system? We just had one installed several weeks ago and been having nothing but problems.

    1. ZenHomes | | #17

      Can you share more details of the installation and problems?

    2. Jon_R | | #18

      Can you post the design schematic for the system? The one that was supposed to be sent to Chiltrix prior to installation.

  16. jameshowison | | #19

    Does the outdoor unit have to run a periodic "defrost" like the outdoor units on the minisplits? I found those surprisingly loud (not to mention that the indoor units stop blowing, then start again).

    I'm also wondering if those using radiant ceiling panels with the Chiltrix (or other systems, I suppose!) can discuss whether there are expansion and contraction noises (clicking etc) associated with them.

    1. ZenHomes | | #20

      Yes, the outdoor unit runs defrost cycles when it needs to clear the coils - see the ~6 minute spikes before the unit runs a heating mode cycle. I have not paid any attention to the noise during defrost but it is unit is quiet enough to not even register from a short distance.

      My design uses a buffer tank and fan control that smoothly matches blower speed to the hydronic coil temp, hence there are inherently no jarring indoor unit start-stops.

      I built radiant ceiling panels for four bedrooms using [URL=]John Siegenthaler's detailed article[/URL]. No clicking noises in heating or cooling mode if you follow the instructions.

  17. ZenHomes | | #21

    Yes the unit runs defrost for about 6 minutes when required, usually followed by 45-60 minute heating cycles, depending on outdoor conditions. The outdoor unit noise when defrosting is no different from when it is running full out, not really noticeable from a short distance away.

    My design uses a buffer tank and a variable speed blower which smoothly ramps to match hydronic coil temp, hence inherently it does not have any jarring fan start/stops.

    I built four room ceilings using John Siegenthaler's detailed article No clicks in either heating or cooling mode.

    1. Expert Member
      NICK KEENAN | | #22

      Are you doing radiant ceiling cooling? Tell us more about how it's installed and how it works. How are you doing dehumidification?

  18. ZenHomes | | #23

    Yes, radiant ceiling cooling was in place this summer, fabrication exactly per the Siegenthaler article. Chilled water from the Chiltrix outdoor unit goes straight to a MagicAire hydronic air handler which takes care of dehumidification. Chilled water for the manifold supplying ceiling loops uses a mixing valve to keep ceiling temps at least 4 deg F higher than indoor dew point. This summer the mixing valve was manually set at high enough offset, next summer will have a controller adjusting mixing valve at 4 deg offset in real time, as measured by an RHP-2W44 dew point sensor.

    1. Expert Member
      NICK KEENAN | | #25

      Thanks, and the next question... How is the air handler ducted? Do you have ducts that serve the whole house? It would kind of take away a lot of the appeal of hydronic cooling. If not, how do they run?

      This sounds like the dream system, no noise, no ducts, no vents, no radiators, no drafts. I 'm just trying to get an idea of what the realities are. Thanks.

      1. ZenHomes | | #26

        The house was originally built with forced air heating/cooling. The old furnace was replaced by the hydronic air handler and all accessible ductwork was sealed. The envelope of the house was also air sealed to extent possible to bring the heating load within the capacity of a single chiltrix unit. The radiant ceilings now create a level of thermal comfort that was pretty much unattainable by forced air alone. While radiant alone would be fantastic in dry climates, our mixed humid climate requires dehumidification. The beauty of using chilled water is that a very low continuous airflow can be used to wring out moisture while the chiller linearly turns down as needed to match latent cooling demand, running at as low as 25% of rated capacity.

    2. mjezzi | | #27

      Just stumbled on this thread. What controller are you using to control your mixing valves?

      I was originally looking at a Messanna system but it was too expensive. This sounds more affordable and isn’t proprietary.

      1. ZenHomes | | #28

        As far as I know, there are no off-the-shelf controls available to handle this application. You have to be comfortable building the system using a mix of industrial controls - Dwyer RHP dew point sensor, Honeywell U2016 controller and Danfoss mixing valve. New prices can be quite expensive but surplus equipment off of Ebay is the answer if you have patience.

  19. jameshowison | | #24

    We considered going this route, but were concerned about not having anyone who could service equipment if there was a problem. We also had humidity concerns, but we did end up getting a whole house dehumidifier (UltraAir 98H) and even in our pretty leaky house in a humid climate there is no trouble setting and keeping a particular dew point, so I wouldn't have concerns there in the future.

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