Plumbing in the Home/Type "D" Copper Tubing?


donhleo wrote at 2006-07-15 03:00:40
I am just a condominium owner  with no expertise in plumbing.  However we here have had 5 major pinhole leaks in our copper pipe systems over the past two years.  I have researched the subject, talked to experts, talked to people from Alaska to Florida and have found no solutions.  No one knows what is really happening and there are no relly good solutions except one.  Replace all copper pipes with PEX or some plastic piping.  

becool wrote at 2006-10-10 16:26:14
There is a thinner copper pipe - Type D which is used for heating and also a DWV. It is thinner than type M, making the plumber correct in this case.

Bryan wrote at 2006-10-17 13:16:16
ASTM B447 -93 -- Standard for Welded Copper Tube

My copy is revision year 1993.

section 10.4 Wall Thickness Tolerance - wall thickness of the tube shall conform to the tolerances listed on Table 5.

(Wall thickness agreed on by manufacturer & purchaser)

ASTM B-88 -95a -- Standard for Seamless Copper Water Tube.  My copy is revision year 1995.

Table 1 has the dimensional values for Type K, L, & M.

(example, 3/4 M wall is .032" 3/4 L wall is .045")

Smokes wrote at 2007-06-15 02:19:46
There is "D" copper Pipe. It is DWV(Drain Waste and Vent)pipe and it is the thinner then type M

From thickest to thinnest





Irwin Energy Consulting Services wrote at 2007-12-30 14:37:14
Type "M" copper piping is a thinner wall product and is recommended for residential heating where the water is not changing and the average pressure is beloe 30 PSI

Type "L" piping is used for hot and cold water  distribution within a structure.

Type "K" copper has a heavier wall thickness and is usually used for under ground services supplying water from the town water main to just inside the foundation. Many suppliers supply this product in 66' coils as this appeared to be the average distance from the town water main extending to the inside of the foundation.

DWV copper tubing is used for plumbing sewage  drainage systems.

I have encountered copper tubing that appeared to have been installed, I assume during the second world war? It appeared to be very brittle and had a thin wall. I discovered this via high tech research. I grasped the pipe and gave it a slight pull (not sure why) and it snapped off in a basement. Yes, there was an endless flow of water.

Dale Cook wrote at 2008-04-21 03:20:59
I am a plumber apprentice in Minneapolis.  So there is a lot I do not know.  But I have run into type "D" 3/4" copper 3 times while installing water heaters in the western suburbs.  When trying to use a tubing cutter on it there was no amount of slight pressure that would not cause the pipe to crush and deform.  The stuff scared me to death.  What I did was use extra-long repair couplings approx 3" long to slide well over the existing stuff and sweat in type L.  I don't profess to know the real story but it said type D on it.  And it was paper-thin.  Thank you

ContourN wrote at 2008-09-12 20:38:34
I worked for a plumbing wholesaler in Minnesota in the 70's and 80's and they did indeed have copper tube called type "D". Prices were rising on copper so they came out with a new type with nickel in it or something. Thinner walls than type "M". Pin hole leaks can happen in any type copper. There's a lot of debate about what causes it. Wiring, grounding, a change in the chemicals the city uses etc.

pipey wrote at 2011-06-05 22:32:25
I worked for a plumbing wholesaler in the 70s and 80s. When the price of copper started climbing they came out with a type D copper tubing that was a thinner wall, had some nickel or something in it I believe. It was definitely called type D copper tube.

Kirk wrote at 2014-03-29 00:13:20
I have had several pinhole leaks in my copper water pipes. I had to replace all the copper water pipes leading to the kitchen and two bathrooms with plastic. Luckily they all are located in just one interior wall. All the defective copper was made by Anaconda. My plumber told me that there was a bad batch of copper or a bad run of pipes by Anaconda in the 1970s when my house was built. I've had to replace two walls and one ceiling. Most recently another that we hadn't replaced as it only led to the refrigerator feed sprung a leak. Again Anaconda. All in all, replacing these defective Anaconda copper pipes has cost me thousands of dollars and dozens of hours. I am curious as to whether there was ever a class action lawsuit against Anaconda for selling defective product.

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