How Many Gallons Per Foot?

[Stayouttadabunker]

Or...How many feet per gallon? haha!

I'm trying to calculate how long the pipe lines are in a floor slab.
The piping is the old gray 3/4" pre-PEX pipes.
I ran about 12-1/2 gallons of water through it to have water come out the other end.
If my math is right, 3/4" pipe holds about a gallon for every 43.33 feet of 3/4" pipe?

So, with 12 gallons going through it, the pipe is about 500" right?
Give or take about 20 feet allowing for the air that probably ran on top of the water inside the pipe as I ran the water through horizontal-laying pipes in a concrete slab?

[HayZee518]

volume of a cylinder equals area times length in inches.
area equals pi times the radius squared
.75 divided by 2 equals .375 pi equals 3.1416
.375 X .375 X 3.1416 = .4417875 X 12 inches = 5.30145 cu in per foot
multiply 5.30145 times length of 43 for cu inches in that length so -= 227.96235 in 43 ft of pipe
now find how many cubic inches in one gallon of water

[Stayouttadabunker]

I cheated...I found a chart that says there's 231 cu in. per gallon...lol
2.5 gal. X 231 cu in. = 577-1/2' of pipe in the slab and out to me!
Since I'm about 35'-40' away from the point-of-slab, it would make a good guess that there's about 500' of 3/4" pipe in the room slab!

What the BTU output of that pipe in a slab when the room is heated to 70 degrees is another question to ponder...lol

I would need exact room dimensions and R value of insulation, windows, etc.
So much to learn and I'm already 51 years old! Arghhh!!! LOL
You gotta love it!

Link to chart I found...>>>

http://www.asknumbers.com/CubicInchToGallon.aspx

[HayZee518]

is there any way you can find out how the cpvc is run in the slab? was it non flexible pipe or flexible cpvc put in before the slab was poured? flexible would start at the manifold - go out and loop a few times before coming back to the return manifold. non flexible plastic uses fittings, threaded or not threaded just glued. you might have 500 ft or more.

[Stayouttadabunker]

I could try and get in touch with Neil Windsor Refrigeration out in Colorado.
He might know as he was the Cantherm installer.
He had lost his notes on this job but maybe he might remember
how the pipes were laid.
My guess is that the slabs back then were thicker than nowadays
and they probably laid down rolls of cpvc and spread out the roll flat as possible.

I have a idea how to determine the exact length of piping used though -
with a fishing pole, some fishing line and a little 3/8" plastic ball...

[HayZee518]

take a ride to the county clerk's office or the assessor's office and ask them for a plot plan of the property. once you've located that find out the name of the architect that designed the house. then go to him or her and see if they can find the blueprints of the house and who did the plumbing. there must be a plan somewhere of how the slab piping is laid out along with specifics of what was ordered and installed in the slab. you should be able to find also the slump level of the concrete poured and what weight they poured [i.e. 3000# or 6000# test]

[Stayouttadabunker]

take a ride to the county clerk's office or the assessor's office and ask them for a plot plan of the property. once you've located that find out the name of the architect that designed the house. then go to him or her and see if they can find the blueprints of the house and who did the plumbing. there must be a plan somewhere of how the slab piping is laid out along with specifics of what was ordered and installed in the slab. you should be able to find also the slump level of the concrete poured and what weight they poured [i.e. 3000# or 6000# test]

Thanks HayZee!
Marc Camens designed it...I have the original drawings but it doesn't include the details.
With the cracks in the basement floor, and cinder block walls caving in - it was probably 1000# test...
I better move...lol

[Stayouttadabunker]

Found another chart from Amtrol.
I was looking at Float Type Air Vents and the one I have is #732.
Good for 45psi.
Anyways, this Amtrol chart contradicts some of my calculations on the length of 3/4" pipes in my slab?
Click on chart to enlarge if needed...>>>

[thurst]

Dont' forget to carry the 1

[Speedbump]

Not all 3/4" pipe has exactly 3/4" ID. If your really going to use this method, you should actually measure the pipes ID.

[Stayouttadabunker]

Not all 3/4" pipe has exactly 3/4" ID. If your really going to use this method, you should actually measure the pipes ID.

The piping is the old gray 3/4" pre-PEX pipes. (circa 1986)
I mentioned this in the 1st post of this thread.
I did NOT measure the I.D. of this piping.
Do you know offhand what it may be?

[Speedbump]

I have no idea, that's why I recommended measuring it.

[Stayouttadabunker]

I'm happy with my guess...
I'm not a rocket scientist and it's good enough for me.

As for your suggestion...Thanks, but I guess I should have measured the I.D. before I put it all together?
I don't feel like taking it apart right now while it's full of hot anti-freeze, 11 degrees outside and working fine. Nooo....

[Speedbump]

11 degrees outside and working fine. Nooo....

That's why I live in Florida.

[Redwood]

3/4" PEX would have an ID of .671"

But Grey is an indication that you have Polybutylene...

PEX is an SDR-9 tubing, and Polybutylene is an SDR-11 tube so the ID will be larger than PEX...
The OD will be the same for both because it is "Copper Tube Size"