Posted by Bud...Suncoast Plumbing on June 04, 1998 at 18:06:33:
In Reply to: Using Type M 1/2" copper pipe in a heating system. posted by Ralph V. Emmerich on June 01, 1998 at 19:44:59:
Ralph:...As you know, copper pipe is supplied in three grades.."K"-"L"-and "M" they may be termed "Good-Better-and Best".
In this order , "M" is a very acceptable material for all general purpose applications. If the pipe is to be buried under concrete or in an otherwise inaccessible area, prudence dictates that a more durable (thicker) grade be considered. Type "K" copper is the product of choice on jobs where price is not a consideration (City-County-State or Federal jobs)
A few years ago(25?) there was a grade of copper called "Distribution Copper", and had a white stripe on it for identification. This type of piping is no longer manufactured (to my knowledge) because of many early failures due to pin hole leaks......Bud..r