Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.


Singh_9 Member Posts: 24
Pictures, schematics etc..?

<A HREF="http://www.heatinghelp.com/getListed.cfm?id=377&Step=30">To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"</A>


  • Yea, you know what...

    Not a sign of sweat anywhere either. Very very cool. Literally. Control is a little tricky when it's cool and humid outside because the space wants to overcool when dehumidifying. It may have had something to do with added humidity from taping and painting but now that it's a bit warmer and humidity inside has come down space temp is staying right at setpoint. Apparently sweaty floors will be a non issue. A good inexpensive control to work the system even more accurately would be a nice thing for someone to come up with. I'm using Honeywell's IAQ and the "Away Dehumidification" mode is a pretty close fit but not perfect. With a little tweaking of the software I thing it could be a hit though. I plan to call them on it.

    Now I must go do the Happy Dance!
  • Not much to see...

    Concrete with tube in it. Wirsbo manifold(s). Smallest Unico A/H (1218CW)there is for dehumidifying and it's knocked down to probably less than a ton. (For 2250 sq ft)Slowest speed with dampers to further restrict the air. Heat-flo buffer/hydro separation tank. very nice but the smallest they make is 45 gal and it's a pricey little bugger. Robur GAHP feeding the tank and Taco 009s to feed the floor and A/H.

    The "Away" mode allows me to dehumidify down to 55% (wish it was 50%) and it will shut down dehumidify if room temp goes below 70* (wish that could be a smidge lower as well so I could dehumidify on the cool wet days). I was working it in regular mode because I wanted to drag the moisture out of there and the room temp was 67* (naturally) when I first started it. The customer kicked the dehumidify back to 65% because it was getting too cold so that's where it was when the floors kicked in and there was no sweating at all. Just a bit on the supply side of the manifold which went away after a while.

    So it was 70* and 65% humidity in there today and they were loving it but I could feel it was a bit clammy so I went to away mode and set it up 55% and 70* lower limit. Room temp setpoint 72 at the moment but the hope is, once it dehumidifies more, we can up that a few degrees. So we're taking it slow and still tweaking. Definitely works well though!

    If you're tricky you can wire the IAQ to a Taco SR type control box without too much effort. Just use the Taco outputs for 24V and then it takes only one wire from each output on the IAQ module to the correct terminal on the SR box to pull the relays in. I even cheated and used one of the relays to call in the A/H as well. Worked out pretty slick. I was feeling mighty darn clever when I finished wiring that puppy up and it worked. I set it up so the A/H is both dehumidify AND 2nd stage cool. Floor is 1st stage cool. ;-)

    To my knowledge it's the first job in the US running radiant cool in a commercial application. Kali got the first residential one, CT got the first commercial one.
  • Paul Fredricks_9
    Paul Fredricks_9 Member Posts: 315

    Way to go M. When do we get to hear some cool, comfortable music coming out of there?
  • Very soon!

    I think. lol...

    When I hooked up with him yesterday he was studying the NEC book because the budget went south and he can't afford to hire an electrician to finish. I'd say he's around 80% at this point but the major stuff is done in the main studio.

    BTW!! MARPROG at toads this Sunday. If you want to come email and I'll comp you a couple tix. ;-)

    Let me know if you want to come up for a looksee some time too!
  • Paul Fredricks_9
    Paul Fredricks_9 Member Posts: 315

    Got a gig Saturday night in Southport. Usually a late night. We're also getting ready for vacation. I'll have to play it by ear. Hope it goes well. If I make it down I'll look you up.
  • Dave Larsen_11
    Dave Larsen_11 Member Posts: 39
  • GMcD
    GMcD Member Posts: 477
    Commercial Radiant cooling in the US

    Check out what Davis Energy Group has been doing in California- there have been operating commercial radiant cooling projects out there since the mid-late 1990's. The first "large" scale commercial radiant cooling system was installed at Pier One in San Francisco in 1999, and it's been working well since. That building is right beside the Ferry Market building there, where the passenger ferries come in just west of the Oakland Bay Bridge.

    The first large institutional radiant cooling slab system in Canada was installed in 2001 at the ITC Building at the University of Calgary - a bit of a hybrid system, but still a large scale radiant cooling system in a multi-storey building.

    I've been designing radiant cooling systems for the last 10 years out here on the Wet Coast (Pacific NW) and there are many large scale commercial and institutional radiant cooling systems now operating out here. I am just going out tomorrow afternoon to do the One Year warrantee review at the City of North Vancouver Library project - horizontal slinky coils under the slab on grade and side-cuts of the underground parkade, feeding a W-W heat pump plant and two dedicated outdoor air units (DOAS) on the roof. Made it through the first winter and a couple recent hot spells with no problems.
  • Really? Oh well,,,

    First I've heard of any of these so my mistake. I'll take a look at them. If anyone wants to give me (us) the lowdown on their control strategies I'd love to read along. I find it very surprising that when I went to every control vendor at the big expo in NYC (last year?) at the Javits Center and asked about ways to control a radiant cool system they all looked at me like I was from outer space. I had no idea anyone else was involved here in the states. Even my local suppliers thought I was totally bonkers, risking it all, it won't work, etc etc... I'm still happy it works but now I'm sad cause I'm not first. :-(

    Oh well, can't have everything. ;-)

    I set up the floors for the heat load 5/8" HePEX on 12" centers and I'm just putting cold water to it so there was no real good calcs for cooling. I'd also love to hear about any means to more accurately determine the cool load in terms of radiant.
  • GMcD
    GMcD Member Posts: 477
    General Ignorance in the industry

    I'm not surprised you get the "deer in the headlights" looks when you've asked about radiant cooling systems. It's not been applied very well in the past, nor has it been supported by many people in North America. Check Dr. Stan Mumma's website at Penn State - lots of good info there, mainly on suspended radiant cooling panels and Dedicated Outdoor Air Systems (DOAS).

    A couple years ago the Clinton Library got some press on it's radiant floor cooling system, as another large scale commercial radiant cooling system. Google guys like Peter Rumsey, Peter Simmonds, and myself to see what we've been doing. Lots of info out there. Flack and Kurtz have been doing some radiant floor cooling systems, as well as Interface Engineering out in Portland. The new Vancouver Convention Centre out here has over 400,000 SF of radiant floor system in it.
  • yep,

    My Unico supply house person was literally chewing me out because he was so A. Ignorant on the subject and B. Worried I was going to end up with my butt in a sling when it didn't work. I spent more time allaying HIS fears than I did mine. Really, took me a few times explaining everything to him before he calmed down over it. I finally just got mad back and said, "Look, it'll work, OK?"

  • Paul Rohrs_4
    Paul Rohrs_4 Member Posts: 466

    I have also been waiting for an integrated control before I moved into this market.

    Glad to hear your success story. I have not invested the time yet to wrap my brain around the sizing of said cooling systems.

    Nebraska and high humidity go hand in hand here and I just think some logic has to be involved even when base load or 1st stage cooling is deployed. IE- floor temp is corrolated between dew point, outdoor temp, and water temp.

    I have had no training on radiant cooling but look forward to accredited training courses.

    Still would like to see pics MPF.


  • There IS a control out there that does that.

    I BELIEVE Danfoss was making it and then sold it to a company in Denver. I'll have to dig around for the info, I have it here somewhere. However VERY pricey like $2K - $3K, can't recall anymore. It would have been a deal breaker if I tried to include it. I would have needed two. My idea has been let dehumidification lead the way. It works ok but it certainly could be made to work better with a logic designed as you describe. It's supposed to go to 90 and be humid here Friday so I'll be out there checking it out. I'll get some pix for you all.
  • Control info:

    Found it! I got a name here **** Barnett at 303-322-1858. There's another number here 303-618-4109 but the first one is in a box on my notes with ****'s name. The Control is (if I can decipher my chicken scratches) ECLV (or maybe U) 32O (letter O) which I believe was the control by itself and it is in the $2k-$3k range. Then there's a ECLV32R which comes in a panel all prewired and THAT was $4K+. Those prices were from about a year ago. I'm giving ranges because I know Dan doesn't like us talking prices. Hopefully he's ok with it. If not he should let me know and I'll pull them out of the post.
  • Nice Job MPF

    There is nothing better than cooling a building to the core. What temperatures are your floors running? Couldn't we just put a dewpoint sensor in the floor surface that would shut down the floor loop while allowing the fan coil to work? This is the ninth season for my radiant cooling system, but it has only been on for two days this summer.

    Thanks, Bob Gagnon

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • Well,


    The air from the Unico units blows straight down onto the floors so they are "washed"(if you will) with the dehumidified air. I think this will further prevent any possibility of sweating. I didn't take any readings while I was there because the same thing is happening here to us, not much heat yet, so the floors were not running while I was there. I felt them and they felt cool but I can't say the coolness was leftover from when they ran. I'll know a lot more Friday afternoon. My thought was if they DO get too cold I'd put a tekmar with a slab sensor into the mix and limit them to like 66* which is supposed to be the magic number. Trouble is, like everything else, tekmars with slab sensors are designed to close on temp drop and I need them to open on temp drop. So I figure I have to stick a relay in there to reverse the action. I'm in wait and see mode on that particular idea. According to the psychrometric chart when the RH is 50% the floors (theoretically) shouldn't sweat until they are ~53* which I believe should never occur but only time will tell. Some reading I did somewhere mentioned that the people involved were TRYING to get their floors to sweat and it wasn't that easy to do. I'm hoping that works in my favor. I HAVE noticed that so far air and floor temp are almost identical. That was the case when I first started investigating the site. On a 95* day the air temp in both buildings was 74* and so were the floors. I found that to be very interesting because I had expected the floors to be cooler than the air. This was the existing concrete before I insulated and overpoured it. I recently took the temps again with just the air running and it was still the case but temps were a bit lower of course.
  • More...

    originally I had thought about putting the floors on a humidistat so that if RH was too high it would shut the floors off but then I thought if you have a very hot humid day and the floors turned off the A/H would not have the output needed to cool the space and we'd overheat, so I canned that idea.
  • I Was Thinking

    That the dewpoint sensor would shut off the floors for an hour or so, until the fan coil could remove some humidity, when it is very humid. My floors with staple up run at about 68 degrees and the room at about 70.

    Thanks, Bob Gagnon

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • Thanks Bob!

    I'm going to go there tomorrow and spend a good portion of the day there so I'll be taking some readings.
  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    At the last Solar Decathalon

    the House from Colorado had a room divider made out of copper pipes. It had chilled water capabilities for radiant cooling. I looked it over and asked where the condensate collection pan was. They said it was so dry in Colorado they didn't need one. I noticed they weren't running it in the very humid climes of Washington DC. :)

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • heh, neat!

    Makes sense.
  • I have pics!

    But no time to post them right now. Sorry! ;-)

    maybe Monday
This discussion has been closed.