Hydronic Ceiling Panels

Kent_3

If a motel room has adequate heating with standard baseboard (580 btu's /foot @180*), would a same-length ceiling unit with 580 btu's /foot @ 180* also be adequate?

Brad White

Probably Not

If I assume a mean water temperature of 170 degrees F. (using for example an Airtex extruded panel system), I get the following "per linear foot" BTU per Hour outputs for the noted panel widths:



6"   =128

8"   =161

12" =212

16" =270

24" = 389

30" =446

36" = 530



There are other sizes in-between (9", 10", 18") but I wanted to give you an idea. Your panels may well cover your ceilings more than 3 feet deep to get the same output.



Now, if your actual heating load is less than you think, you may be able to meet your demand (I have no idea). The comfort effects of radiant may (*MAY*) help compensate for a marginal BTU shortfall.



But if you are struggling with 180F supply water and your fin tube is not clogged, bent or blocked, then you will not make it with the panels.



Edit- I took the question literally, the use of an applied product,  ("hydronic ceiling panels"), not a radiant ceiling. Love radiant! Just that the available applied products are limited in output unless you "go wide, go deep". So the full radiant ceiling gets a thumbs up, IMHO.

Kent_3

but...

I did find a wet, ceiling-mounted radiator, the Runtal CR-7, that puts out 660 btu's /foot @ 180*.  I guess I can re-word my question: does a btu coming radiantly from the ceiling provide at least the comfort level of a btu coming from a fin-tubed baseboard?

Gordy

I will stab with a Depends

 On ceiling height, and water temps. I have ceiling radiant, and love it. My controls are simple. Water temps generally 115* supply.  What I really love is in the dead of winter when sitting in a chair or laying on the couch you can feel it.  Its like the sun shining on you. You do not get that with RFH. 



 Base board is a different animal in my opinion kinda like a cross over from forced air, with convection forced instead of a fan



  But then I have an old school type of ceiling radiant verses the panels you speak of. So those could react differently



 Gordy

Kent_3

Old School radiant?

And what is that, pray tell?

Mark Eatherton

Different means of delivering comfort....

Baseboard is 90% convective (air heating) and 10% radiant (front panel) output.



A ceiling mounted radiator has little to no convective energy, because hot air rises, and if it is already at the ceilings highest point, convection doesn't kick in, so its output is essentially 100% radiant. Radiant heat affects the MRT (mean radiant temperature) and MRT is THE driving factor in delivering good human comfort.



Base board cannot affect the MRT significantly without creating a whole lot of discomfort, because the air temperature would have to be greater than the surface temperatures in order to affect them. Two completely different methods of providing comfort.



If they say it kicks 660 btu/LF, then it kicks at least that much, and probably more when recovering the mass of a space.



Gordy's old school system is copper tubing buried in a cementitious plaster ceiling. Very durable and effective.



CORRECTION: I got to thinking about my comments later and Brads comments as well. My assumption is that the RC panels are intended for ceiling mount only. If they are actually a wall mount panel radiator being applied to the ceiling, then they probably will NOT put out the 600 btu/lf. When mounted low, they put out roughly 60 % radiant, 40% convection, and if mounted on the ceiling, the convection goes away.



But, then again, on the other hand, in my 36 years of hanging out with heating systems, I have never seen a system hit a 100% demand factor even at design conditions, so you will probably be just fine, even with the 40% decreased capacity.



ME

Kent_3

Thank You

Mark,

It sounds like you're pretty confident in the radiant ceiling idea.  Would you be positively impressed if you were to see it in a hotel room you just rented?

Mark Eatherton

I have it in two of my houses...

Biased opinion on my part. I've seen things in hotel rooms that would cause most people to go HUH???



I've seen base board convectors at the ceiling line (Edwards Engineering) http://www.edwardsvalance.com/



It provides heating AND cooling to a given space.



Would I be impressed if I saw it in a hotel room? If I didn't know what I know, I would probably be inquisitive, but if you were to bury the radiant panel to the point that I couldn't see it, and I was EXTREMELY comfortable, I'd probably be even more impressed. Especially if it would (can) also provide cooling...



Personally, I think radiant ceilings represent one of THE most commonly missed opportunities in delivering good human comfort. Not sure why there is so much reluctance. It's been around for longer than radiant floors in many parts of the country.





ME

Gordy

Old school Pic

   Kent here is a pic taken when I remodeled the kitchen. I removed some soffit so the tubing ran through with no plaster. Some radiant floor is always nice with tile in the kichen too.





           Gordy

Kent_3

warming up

Thanks for the pictures - very neat job.  I'm warming up to ceiling radiant.

Gordy

I'm a believer

 It took Mark, and Tom Tessmer (where is he?), and living with the system. To make me understand, and appreciate what I had. I could not get beyond heat rises hurdle 10 years ago when I bought the house, and found this site.



Gordy