I am working on a project that involves the retrofit of an older school (1986) with quite low floor to floor heights as well as a new school design. Active Chilled Beams have been proposed for both. I'd like to get some feedback on this application - specifically any downsides to look for like humidity control, condensation on the coil, relation to envelope infiltration (particularly the old school that we can't really air seal), maintenance issues (coil cleaning etc) or any other comments (pro or con).

Thanks

Some added info - Project is located in south central Massachusetts - near the Connecticut line. Winter design temp about -5 to 0 - summers can be humid.

Thanks

Is this a classroom or office application?

Are you planing to use return air or outside air for the "active" part of the design? If outside air is used, it will need to be treated (dehumidified). Integrated light fixtures?

As you point out, humidity control is a key issue.

Another problem is solar gain or a high skin load. If your perimeter load is greater than ±50w/m2 or so you may need some supplemental fan coils.

How will you handle heating? Chiled beams are cooling only.

Both active and passive chilled beams are widely used in Europe with good success as long as their limitations are recognized.   It probably won't be cheap.

A split system with wall mounted units may be the most cost effective and energy effective cooling system for the renovation although it may not solve the heating problem in your locality.

Bruce

Thanks. The tip on the solar gain is helpful - hadn't really considered that. My understanding is these CB's will be both heating and cooling. As I understand it these usits will be supplied from roof top units with energy recovery. I'm not sure what is proposed for humidity control for the supply air. This project is in Schematic Design and I have no experience with CB's. When you say these will be expensive what exactly is the driver for the cost - is it the unit itself, or is there something else.

Our office experience (Europe) is that active chilled beams with integral lighting installed in a metal panel ceiling is more expensive than fan coils, diffusers, 60 x 60 light fixtures and acoustical ceiling. There are lots of variables however.

In offices, heating for the interior zones is seldom needed and I have no experience with chilled beams in the heating mode.

Just as high solar gain at the perimeter can overload chilled beams in the cooling mode, I am a bit skeptical that they can handle 100% of the skin load in a heating mode. If the enginners can show successful "heated beam" installations, I would like to know more details.

Chilled beams, chilled ceilings and underfloor, displacement air distribution systems are popular in northern EU because they really dislike the air movement associated with conventional AC systems.....actually they would rather just open the window (operable windows can also be a source of uncontrolled humidity that can cause condensation). I think the EU's tolerance for temperature discomfort is higher than ours, and our tolerance for moving air is higher than theirs. Different strokes......

Bruce

I need to see some pictures of the place you are working for, i think i can get a good ideas after that.

Hello..I have no any idea about this thread. Please anyone can provide me complete information.

Well best of luck in finding out projects that you are looking for, hope you succeed in what ever you are in search off....