Valance Cooling

[PagoMitch]

Would anybody on this site have experience with Valance Cooling? See the url in the attachment. Basically, it's a chilled water cooling coil within an aluminum housing, suspended below ceiling height on an exterior wall. No fans.

The concept looks good from an energy use viewpoint, but I question the responsiveness of the system to thermal loads. Condensate may also be a concern. It drips from the coil, onto the internally lined (0.25"/6mm thick rubatex) aluminum housing, and then runs ON TOP OF THE INSULATION to a 3/4"/19mm PVC pipe that is inserted between the insulation and the aluminum housing. The pipe/insulation juncture is then filled with some type of waterproof sealant.

A client would like us to use this in a health care environment, although it looks residential(?) in application to me... The Valance Unit would only handle shell/skin loads, as the room minimum airflow requirements would be handled by a separate conventional supply/return air system.

 

[GMcD]

Or do your sums and see what the cost of higher performance glass and exterior sun shades would be versus the cost of a complete perimeter compensating system, the continual operating costs amd maintenance costs for that perimeter compensating system. Think about purposely causing condensation in a hospital environment - a wet place for interesting things to grow.....

The VA Hospitals have been using passive radiant ceiling panels for heating and cooling at the perimeter - fast response, but no condensation issues, just watch the chilled water temperature and use pipe dewpoint sensors on the CHWS to the radiant panels to avoid condensation potential. And work with the Architect to optimize the window thermal performance, solar performance, and try to get exterior sunshades.

 

[cry22]

Any standard radiant panel will do the job and look just as slick.
I once inherited a Valance design before final submission, I looked at it very closely. I trashed it out (the vendor was furious at me). This thing costs an arm and a leg to do what? cooling?. Nothing justifies its cost. On top of that, you'll get a proprietary system in your hands.

 

[PagoMitch]

The project is a small (10000 sq. ft.) remodel in a 1,000,000 sq. ft. building. Windows are already dual glazed, and they will not permit exterior sun shades or tinting. Building chilled water supply temp 42F. Not changeable for a Radiant System, no floor space available for a heat exchanger/pumps run-around secondary, say 55F Radiant loop.

As I indicated, I (hope) I'm aware of (most?) of the potential problems. But the client will not take the problem list seriously. "The vendor says it will work fine, and I've seen it in a Retirement Home across state. Do it." And yes, I know that a Retirement Home is a far cry from a JCAHO hospital, but the client/manager chooses to ignore this reality.

This is my dilemma. I'd like to find someone who has actually designed, had a Contractor installed, and then lived with (and maybe dealt with) some of the subsequent problems. With maybe pics of mold inside the Valance units, exterior condensation problems, etc. This Valance system alone is pushing $250,000 for this space, and it frustrates/saddens me to know that it's going to be in the dumpster within a couple years.

At this point about my only option is to write my CMA letters...

 

[marcoh]

Only had a quick look at the link but it seems to be a chilled beam located within an enclosure? Thus issues similar to typical chilled beam installation would apply, and if a generic design is used, you should get more competitive pricing.

 

[trashcanman]

Who is signing and sealing the drawings, you or the vendor? If I wasn't comfortable with the system and felt it would fail, I would politely decline to do the project the way the owner wants it. You should not have to convince yourself that it will work. Tough situation, but it is your seal and reputation on the line.