Radient heating & cooling in a big old building
I am designing an application involving a rehab of a big old building into apartments
The space heating loads are roughly 40kbtuh & the DHW loads averages approx 40 KBTUH so I think a small condensing wall boiler should do the job.
I can use a variety of radiators which is a question. I want to also have radiant cooling
The cooling is the concern. The cooling loads are 28 to 35 KBTUH.cooling I would like to provide a hydronic heating /cooling system which would do the job. Ductwork in this application is difficult and this is why the mini-chiller concept with a summer winter control
Can someone comment?
Radiant cooling
Radiant cooling is possible, but it is very hard to manage humidity with. Also btu per edr is generally much lower then in heating mode, requiring more panel surface then otherwise required.
In order to keep from condensing water on the radiators and so forth, the dew point must be lower then the surface temperature of the radiant surfaces.
Also there would need to be radiant panels on the ceiling, or high on the walls to promote convective air currents in cooling mode.
I would look into ductless fan coil terminal units to use in the cooling modes. This would allow for the chiller to provide the de-humidification, and remove the need for duct work.
In order to remove humidity from the space if using radiant cooling, then you would need a separate de-humidification system.
multi-aqua
I've used the Multi-Aqua chilled water console units with great success. Most boiler installation manuals that I have seen have basic schematics for utilizing some of the same distribution runs and incorporating a chiller with the boiler.
http://www.multiaqua.com/
