radiant heat tied into baseboard return line

mikeypmcg

Hello, I have been reading a lot on here today, there is a wealth of information! 

I currently have a radiant heat slab (1st floor garage/ulitlity/laundry) baseboard heat upstairs.  the kitchen / living/ dining room are all one large room with just baseboard on north wall.  the kitchen is on the south side of the house with no heat.  It is a tile floor, and i was thinking of rerouting the baseboard return line with pex tube and running it between the joists under the tile floor.  Is the water in the return line going to be to hot to use with metal radiant mounting panels? should i just mount it to the side of the joists and install foil faced bubble wrap under it? 



thanks

STEVEusaPA

yes.....too hot, no you cant turn the return into a radiant loop.

But you can take a radiant loop off a baseboard loop.  You're going to need to do some mixing to get the temperature lower.  Regardless of the size of the kitchen/tiled area, you're going to have to do a heat loss, and some repiping.  You already have one radiant zone, so whatever you're doing to lower the temperature on that zone(s) you're going to have to do for the kitchen.  If there's a manifold for your radiant, you may be able to switch it out, or add on for the loop or 2 you need for your kitchen, provided your heat loss/load have you using close to the same temperature water.

You're main concern is you don't want your radiant too hot, and you don't want very cool water shocking your boiler.

If you could, take some pics of your boiler, and the near-boiler piping.

If you could provide some square footages of the kitchen, and the other radiant zones, someone here should be able to get you going in the right direction.

Like I said, first you have to figure out how many btu's you need, and how many you can get from the floor

Mark Eatherton

It can be done, but...

Look at Ultrafin. It is compatible with high water temperatures, and might work, but as has been pointed out, everything starts with a good heat loss calculation.



Also be aware that you will affect the hydraulic flows of the existing system. You should probably perform a hydraulic flow calculation for this zone.



ME