Hydronic Panel Radiator placement in a large room

Scott_Mountain_View_CA

I'm heating a 725 sq ft great room with Rutal panel rads. One one end of the room is a long exterior wall. I've read that it's best to position panel rads on exterior walls, but if i did this I would have no panels on the opposite of the 23' long room, an interior wall with heated rooms on the other side. How important is it to put rads on both ends of a large room, rather than placing them just on the exterior wall with windows?

Attached is a layout showing Rutal wall panels under 2 exterior wall windows. There is sufficient BTUH output from these 2 rads to meet great room total heat loss at design. The fireplace is a high quality gas log set which puts out substantial heat (not factored into the heating equation).

Do I need a panel at the opposite end of the room?

Mark Eatherton

I can't open the XLSX spread sheet, so am speaking somewhat blindly. In an ideal situation, you want to place the radiator on the coolest potential wall to raise the MRT, and avoid your body seeing the lower MRT associated with outside walls, windows etc.

With that said, I have successfully placed radiators on inside walls and not received any complaints from the end users. Try posting the picture in another format, and I will try and look at it again later today.

In the radiant floor world, we typically place the highest water temperatures near the outside walls first and work our way inward. I had an errant employee who did a whole house completely backwards, introducing the hottest water in the core and working its way toward the outlying walls. I decided to let it ride and see if the consumer complained. During my first year checkup, I asked the consumer how they liked their system, and their response was "Fantastic comfort"...

I think maybe placement is not as critical as most people would have us believe. My first radiant wall project had ALL the radiant walls on internal walls, and it too works like a champ.

In my own home, I have radiant walls on the inside walls,and although I can sense where the radiant energy is coming from (I am more cognizant about these things than most people) it is nice and comfortable. Of course, I have radiant windows that are on the outside walls, and I think that has a LOT to do with the increased MRT and associated comfort.

YMMV...

ME

hot_rod

Radiant energy travels in all directions at the speed of light.

A good analogy is steeping out of the shade into the sunlight on a cold winter day. You feel the radiant energy transfer almost immediately.

With most panel rads you get both the radiant energy transfer and some convection. The convection will move the heat energy throughout the room.

Scott_Mountain_View_CA

Mark, PDF file attached.

I'm trying to avoid adding a third rad in the portion of the room at the bottom of the drawing due to logistic issues. If I had to install a 3rd rad it would be positioned where noted.

Design temp = 39 degrees. Heat loss = 13 BTUH/sq ft.

Scott_Mountain_View_CA

Bob, were you able to view my room layout? Do you believe the positioning of the 2 rads will provide a comfortable space through the room? Notice the sofa area is not in line of sight to the rads....does this mean that area will be heated by convection and not radiation? Does it matter from a comfort perspective?

hot_rod

Just crank up the entertainment center for additional btu's
Two will work. That 3rd one facing the fireplace may not add enough comfort for the hassle. Cover the load with enough radiator output and the room will heat.

Scott_Mountain_View_CA

Thanks Bob. The 2 rads cover the heat load requirement. I'm runnin' with it.

Mark Eatherton

What HR said. Its a wide open room, so it will work fine. If it doesn't, like he said, turn on the home entertainment system. I use a large flat screen TV to top off my office at my mountain home. Works great and it is on the radiant plane.

ME

Scott_Mountain_View_CA

LOL....my 50" plasma tv heats the room on a cool fall evening. I guess I'm buying expensive Runtals for those 9 annual design days

jonny88

Amazing if this were a job on Long Island your entire room would be wrapped in baseboard.........

njtommy

Sounds like it's time to get a 70" TV. Lol