5/8 Radiant Loop in wall with BB??

anthony_7

I would like to hear any opinions on running 5/8 pex loop (on a 8X10 wall ). Then tie that into about 30ft of baseboard. This on a single zone.

Also is there any calc on figuring how far on center to put the pex.


Reason being is limited on space for BB in bathroom. Thanks

Joe_13

What temp will it run?

You're gonna have hot feet when you run a radiant floor at 180 degrees. Lowering the water temp will lower the BB output for the other room. You'll also be restricting the flow throught the 3/4" BB adding to the drop in output.

anthony_7

In the wall

I was going to run the pex not on the floor and put foil backing behind it. I will run at 180 going out.

Thanks

Unknown

Anthony said

he wants to run the radiant in the wall , not in the floor . I am going to try radiant in the wall also . While at a class for Aquapex , we touched on the subject of radiant walls and ceilings . The seminar host said to design the layout for around 25 BTUs per foot of heated wall . When I asked how far on center the loops had to be , he said it didn't matter , which does not sound right .

Anthony , what are you planning on putting on the wall with radiant ? If its ceramic tile , do the pros know how it will hold up to 160 - 180 degree pex ? Is there an advantage to using one backer over another - drywall , blueboard , wonderboard ? I could use some opinions also with my "project" coming up . Thanks guys .

steve_26

radiant walls

we did a room with radiant high temp.walls using Stadler climate panels and the floor with low temp using mixing valve. The floor is constant circulation conrtolled by a outdoor stat.The wall is on a t-stat when floor can't handle the load on cold days.The room is dry wall and works great.
steve

Frank_17

3/8 pex has the same flow capacity as 3/4 copper

eleft(retired)_3

3/8 or 5/8?

are you basing this on the number of elbows needed to connect copper to baseboard?

al

eleft(retired)_3

5/8 PEX Radiant Loop in wall with BB??

I think, by the time the radiant loop has any effect the baseboard will have heated the space

al

Unknown

where..

the heck did you read this. you better get a new book.

3/4 PEX has the same flow as 1/2 PEX

Einsiedler

agreed

agreed.

Jed_2

Radiant Wall.... 5/8,3/8,1/2, whatever

I don't think I'd be running 180, 160, or even 140F water
in a wall with sheetrock; if that's what you have. You didn't say what the wall construction is going to be. Drywall won't stand up to the Temp. 120F MAX.

Jed

J.C.A._3

Had a job.....

About 12 years ago , to retrofit a boiler in a house that was done in "ceiling radiant tubing". The guy who built the house used to work at the shipyards, and had a thing for horeding "leftovers".

His ceilings were run with monnell 3/8 tubing. When he got to the bathroom, there wasn't enough ceiling space for the loss. He decided to wrap the cast iron tub in the tubing, thereby turning it into a low temp radiator. He also got rave revievs from his wife because she was putting hot water into a already warm tub, and it didn't suck the heat from the water supplied, like most cast tubs do. I figure this guy was about 45 years ahead of the local heat guys! Just one more thing to think about. Obviously, you wouldn't run the tub surround heat at 180°, but at a 90-100° temp, a cast tub could give off enough heat to act as a radiator, and the outlet could give up enough for the base board to make up the rest. Chris

bob young

shipyard plumbers

i might have known that guy!! lol when i worked in the yard in Quincy ,mass. the guys would come up with piping designs that were mind boggling. they even used monel for car exhaust systems. the salt air was not a problem anymore and the exhaust was worth more than some cars. bob n.y.c.