SN
wrote:
Check your references. You have it backwards. Refrigeration tubing (ACR)
is sized by the actual OD. Plumbing & heating tubing is sized by the
nominal I.D. Therefore 1/2" plumbing tubing has an actual OD of 5/8". I
just checked my textbooks to verify this so as not to give dis-information.

Hi -
No need to argue. I just wanted to find out how much water was in a 1/2
inch by 100 foot copper tubing. Just a ball park amount. I was surprised
at just how little an amount of water it is. I am not worrying about
wasting water - I am trying to cut down the time it takes for hot water
to get to my showers. I am surprised it hold less than a gallon of
water. If I insulated that 100 feet of copper tubing - the water in it
will not cool off so quickly. Presently it is running through a 3/4
copper tube that is buried in the concrete slab. It is a double whammy -
since it is in concrete and not insulated - you lose heat thru the heat
sink - and since it is 3/4 copper the tube holds much more water.
Harry