In-Floor Heating

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ijames
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Re: In-Floor Heating

Post by ijames » Sun Sep 28, 2014 4:34 pm

turbobaldur wrote:I find the biggest pain with in-floor heating is it becomes difficult/risky to drill holes in the floor to mount machinery.
If the embedded tubing is on 12" centers, couldn't you use one of those cheap IR thermometers to locate the tubes pretty easily? Never tried it but I think it should work. If you need extra contrast set the thermostat low for a bit to let the slab cool, then crank it up and look for the lines while the hot water is flowing wide open and the slab hasn't warmed up yet. At least that would let you miss them when drilling.

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Re: In-Floor Heating

Post by turbobaldur » Mon Sep 29, 2014 8:32 am

You'd be surprised how good of a thermal conductor concrete is. My neighbour brought in a thermal camera to find a safe place to bolt his ramps to and didn't really have good luck finding the pipes. Maybe he would have had better luck if he cranked the temperature up just prior to attempting that.

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Re: In-Floor Heating

Post by ijames » Mon Sep 29, 2014 9:44 am

turbobaldur wrote:You'd be surprised how good of a thermal conductor concrete is. My neighbour brought in a thermal camera to find a safe place to bolt his ramps to and didn't really have good luck finding the pipes. Maybe he would have had better luck if he cranked the temperature up just prior to attempting that.
Wow. I figured that if even if the $30 thermometer wouldn't have the sensitivity, a real IR camera would have no problem (but at 50-100x the cost I wasn't going to suggest that first :-)). If I ever get the chance I'm going to have to play with my IR thermometer just to see, but right now I don't know of any radiant heat floors near me.

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Re: In-Floor Heating

Post by tubeman426 » Wed Oct 01, 2014 5:33 pm

I have in floor heat and I can feel the pipes with my hand when it first warms up, when I turn it on in the fall.

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Re: In-Floor Heating

Post by user-3597028 » Thu Oct 09, 2014 12:43 am

I'm building a new 40X60 workshop at the lake house right now. We installed Pex tubing in the floor. 10X 250foot runs. You don't want to exceed 250 feet on a run if possible. They get cold on long runs.

I did 5" of 5000# concrete with fiber mesh. The water tubes are attached to the wire mesh. The wire mesh is up on 1 1/2” chairs to put the tubing 3” below the surface. We insulated the slab with 2" of foam on the bottom and sides. We used zip strip instead of saw cutting. This is a two story structure.

The chairs are "mesh ups" and can be stepped on. They spring back up. Very good product. We poured it in Monday with no problems.
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Re: In-Floor Heating

Post by wagspe208 » Sun Oct 19, 2014 11:26 am

So....
My building was built before concrete.
I used 5/8 tubing, on 1' centers. With larger diameter tubing, you can use longer runs with farther spacing. I used 500' rolls.... I have 2000' in the "shop" side. The "storage" side is less sf, but will be 1500' of tubing. The "runs" were limited to 500', so I have a manifold with 4 ports for shop and 3 ports for storage. I then have 2 "zones" and can keep storage at a cooler temp. I willl divide the two rooms with a wall.

We wheelbarrowed 38 yards of concrete over the tubes. Layed plywood down, no issues at all. This stuff isn't as fragile as people would think. It can EASILY be cut, so no sharp edges where wire mesh overlaps.

I bought my tubing, pumps, etc from http://www.blueridgecompany.com/. Very knowledgeable. Spend much time talking me through the process. I'd recommend them. You may find cheaper sources. I have not found a better place to deal with, info, etc. They gave me a "map" of tubing layout. This would have been a huge PITA.
I'll post a pic of the manifold.
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Re: In-Floor Heating

Post by af2 » Tue Oct 21, 2014 4:42 pm

wagspe208 wrote:So....
My building was built before concrete.
I used 5/8 tubing, on 1' centers. With larger diameter tubing, you can use longer runs with farther spacing. I used 500' rolls.... I have 2000' in the "shop" side. The "storage" side is less sf, but will be 1500' of tubing. The "runs" were limited to 500', so I have a manifold with 4 ports for shop and 3 ports for storage. I then have 2 "zones" and can keep storage at a cooler temp. I willl divide the two rooms with a wall.

We wheelbarrowed 38 yards of concrete over the tubes. Layed plywood down, no issues at all. This stuff isn't as fragile as people would think. It can EASILY be cut, so no sharp edges where wire mesh overlaps.

I bought my tubing, pumps, etc from http://www.blueridgecompany.com/. Very knowledgeable. Spend much time talking me through the process. I'd recommend them. You may find cheaper sources. I have not found a better place to deal with, info, etc. They gave me a "map" of tubing layout. This would have been a huge PITA.
I'll post a pic of the manifold.
Wags
I will never go more than 300' on a run because the water temp is done beyond that point. My runs get stacked at 6" centers on the outside wall for a 24" wide or 4 passes and then go to 9" centers for the next passes. Don't know if that makes sense but I pack the outside walls for heat loss as was and is advised from the engineering firm I use to stay at 9" through out.
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Re: In-Floor Heating

Post by wagspe208 » Wed Oct 22, 2014 10:02 pm

Do you insulate the outside walls?
I assume different construction than my little pole barn.
Wags
300' run with 1/2 is much different than 300' run with 5/8 or 3/4. The diam of tubing enables it to carry more btu's.
Engineering firm better go back to school.

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Re: In-Floor Heating

Post by af2 » Thu Oct 23, 2014 2:44 pm

wagspe208 wrote:Do you insulate the outside walls?
I assume different construction than my little pole barn.
Wags
300' run with 1/2 is much different than 300' run with 5/8 or 3/4. The diam of tubing enables it to carry more btu's.
Engineering firm better go back to school.

I hope he did insulate the walls. That looses more heat than the earth.

I didn't catch the 5/8" tubing size, you are correct.
GURU is only a name.
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Re: In-Floor Heating

Post by user-3597028 » Sat Nov 15, 2014 1:33 pm

Stacking wood on the concrete with a bunch of buddies.
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Re: In-Floor Heating

Post by Splitter » Tue Dec 02, 2014 11:19 pm

ijames wrote:
turbobaldur wrote:You'd be surprised how good of a thermal conductor concrete is. My neighbour brought in a thermal camera to find a safe place to bolt his ramps to and didn't really have good luck finding the pipes. Maybe he would have had better luck if he cranked the temperature up just prior to attempting that.
Wow. I figured that if even if the $30 thermometer wouldn't have the sensitivity, a real IR camera would have no problem (but at 50-100x the cost I wasn't going to suggest that first :-)). If I ever get the chance I'm going to have to play with my IR thermometer just to see, but right now I don't know of any radiant heat floors near me.
I just checked this out in my shop with an el cheapo IR thermometer. Outside temp -2F, indoor temp 50F, glycol temp 71F, pipes are 1/2" oxypex 12" on centre in 260' loops, concrete is 6" thick 4500psi with pipes at a depth of roughly 3". I can clearly tell where the pipes are, temp varied at the point measured from 54F directly over the pipe to 52F at the midpoint between pipes. Not much of a difference but it was consistent across 6'. I also checked temps parallel to the pipes, no difference across 6'.

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Re: In-Floor Heating

Post by ijames » Tue Dec 02, 2014 11:35 pm

Thanks for the data, Splitter. I'm glad it was you and not me, doing the test at -2F :-).

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Re: In-Floor Heating

Post by Splitter » Wed Dec 03, 2014 11:05 pm

Hey no problem, winter has been not bad so far. This time last year it was cold enough to freeze your eyelids shut. Can't wait to get the wiring finished and the equipment in place, then I get to find out how much shop time the wife will let me get away with.

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Re: In-Floor Heating

Post by Splitter » Sat Jan 03, 2015 2:11 am

image.jpg
Here's a pic of my radiant heat system: 5kw electric boiler, 3/4" copper plumbing, 1/2" pex pipe (2 loops), circulating pump, expansion tank and air strainer. System is pressurized to 15psig static. I put the pump before the boiler, usually it's after the boiler but I figured this way the pump runs cooler, also more pressure in the boiler can't be a bad thing. The controls in this boiler use indoor temperature for on/off control, and outdoor temperature to regulate the temperature in the boiler, so that the circulating glycol is at a lower temperature when the weather gets warmer.
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Re: In-Floor Heating

Post by les327 » Sat Mar 07, 2015 9:56 pm

blockislandguy wrote:Gee, 200 gal of propane at $4 a gal and 4 cords of wood, say at $125 retail value , cut, split and delivered totals $1300. That sounds high for small shop in PA.
The wood is free excluding labor!!! This year i used 5 cords and around 70 gal propane! The walls and roof have blown in insulation about 6 " in celling (want to add 6") keep it around 60 ,,,,,well 55.
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