True Test of Hydronic Heat

[51Magnum]

Ok, I am about ready to start pouring my footings, stem walls, and then slab. My shop will be 26 x 45. I have four loops of 1\2" tubing that I will staple directly to the 2" insulation. I will have two heat sources, one is the hydronic and the other is forced air (I have been given a forced air unit).

Here is my proposal. I have access to very cheap temperature sensors. I am going to put these things all over the place. First, I will put a humidity\temp sensor outside. Next I will put a temp and humidity sensor inside the main area of the shop. I am thinking I will then put one 6 inches deep under the 2" foam and another one directly under the foam. Next, I will put one on top of the foam and maybe one in the center of the slab. I will then repeat this numerous times around the floor. I would also like to put some in the stem wall and see the heat transfer between the slab and the wall (still need help with how to insulate that, but that is another thread).

What would you like to see? I can lay the tubing in any pattern. We could try all kinds of tests. Some things I would like to see

1. What happens when the garqage door is opened. Which system responds better.
2. What is the heat distribution.
3. What is the time it takes for each system to stabalize.
4. Can you modulate the loops to make it more effiecent.
5. How much heat loss actually goes into the ground under the slab.

Any thoughts? Maybe I am too big of a geek but I think this would be really good to see.

 

[sneezer41]

I have no idea what you are going to measure under the slab. Nothing interesting I would think, unless you want to do it for a couple of years without the heat on, it won't tell you anything useful [scientifically speaking]


The tube should not be stapled down, it should be in the concrete.

If you are going to put both systems in, just use the floor to keep the sin off, you could cycle it a few times a day and the floor will stay warmish, a big plus.

Keep the air off until you go out there to work and flip it on.

It will come up quick because the floor is warm and you will have the best of both worlds

 

[tcianci]

I have to ask... so you monitor the **** out of it...once everything is literally cast in stone, what can you do about it. Any data you gather has undoubtedly been gathered already by the people who design and manufacture the heating equipment, probably under better conditions than you can provide. As the previous poster stated, your best bet is to use the radiant to take the chill off the floor and the air to actually heat the building. Radiant heat is slow to recover and not really intended to be used to heat up a building quickly. It is however, the cats *** when you're down there on a creeper. I have a Beacon Morris hydronic unit heater in my garage and although I wish the floor was warm, this thing heats the room really fast and that what I needed because I do not keep the heat on all the time out there and it's plenty fast for when I want to go out there and work on short notice.

 

[Bigrhamr]

I think it's a great idea. One of the most asked questions seems to be about insulating under the slab. If you have a sensor on top of the foam and under the foam and take a baseline temp with the heat off, then turn it on and moniter the time it takes to heat up and particularly the temp difference above and below the foam it would answer a lot of questions about that. If you really want to get carried away you could insulate some with 2", some with 1", some not at all and some with the bubble wrap. It's true that this type of test has been done but when you read the results you never know who is paying for the test if you know what I mean.

 

[tatra]

contact a local college or school and see if they are interested in collecting the data...........we have a coupla bridges that are monitored.........you could have a smart slab...........

 

[51Magnum]

I would like to see the test with the foam as well. I have been trying to follow all the radiant threads and everyone and their brother has the "correct" answer. I really have learned a lot on this site and love all the input.

I would like to put one loop stapled directly to the foam and another raised 1" off. I keep hearing how it is wrong to staple the tube down but I would like to see some data as why. I can not think the arc that is touching the foam (which is very short) loses that much efficiency. Especially when it is against 2"foam.

I am not sure what all I can gather from it. Other than I can say I did Also, I will try and switch it to solar one day and would like to see the comparison between the two.

I could go with different thicknesses of foam etc. but I really do not want to jeopardize the performance for the scientific community.

 

[redsky49]

If this can be done at no cost, I would suggest the following:

Indoor temp., 12" A.F.F.
Indoor temp., 72" A.F.F.
Interior walls
Exterior walls
Temp at exterior corner
Interior corner
At garage door floor
At peak ceiling height

A couple things you could monitor is consistency of temperature across the slab, stratification of air, entering and leaving water temp, etc.

None are critical, but may be of interest.

As always, offered only as opinion