Options for Copper Tubing

• Copper tubing is used for water, gas and compressed air applications. bricolage.. image by Claudio Calcagno from Fotolia.com

  When upgrading your plumbing, heating or cooling systems, you have several options with copper tubing. Copper plumbing is durable, usually has a 50-year warranty and is designed to adhere to strict standards set forth by the American Society for Testing and Materials (ASTM) organization, an international organization designed to develop consensus standards for a variety of building materials. Most copper today is made from 99.9 percent pure copper and is completely 100 percent recyclable.

Forms

• Copper tubing comes in two forms. One is called hard or drawn copper, which is the kind you usually see in home improvement stores sold in various lengths of straight pipe. The copper is hard and does not bend. The other form is soft or annealed copper and usually comes in rolls of various lengths. This copper is more flexible and bends over a wide arch.

Types

• Copper tubing comes in six types, each with different diameters, characteristics and uses. Type K is used for domestic water supply, fire protection, snow melting, compressed air and vacuum. Type K tubing comes in both hard and soft forms, available in 12 to 20 foot lengths and measures 1/4 inch to 12 inches in diameter. Soft Type K copper also comes in 40 to 100 foot coils and only up to 2 inches in diameter.

  Type L, which is thinner than Type K, is used for natural gas, fuel/ fuel oil, and liquefied petroleum (LP) gas. It comes in straight lengths 18 to 20 feet long, measuring 1/4 inch to 12 inches in diameter. Annealed Type L tubing comes in coiled form, 40 to 100 feet long and will only measure up to 2 inches in diameter.

  Type M copper tubing is thinner than Type L, comes only in straight lengths of hard copper tubing, and measures 1/4 inch to 12 inches in diameter. The copper tubing is used for underground water services, water distribution systems, chilled water mains, and water heating and low-pressure steam.

  DWV copper tubing is available in straight 20-foot lengths only, measuring 1 1/4 inch to 8 inches in diameter. It is commonly used for drainage and waste systems, ventilation and HVAC systems.

  ACR is for air conditioning and refrigeration systems as well as natural gas and compressed air. In straight lengths, ACR copper tubing measures 3/8 inch to 4 1/8 inches in diameter and comes in 20-foot lengths. ACR also comes in 50-foot coils and measures 1/8 inch to 1 5/8 inches in diameter.

  OXY/MED copper tubing is for medical gas and compressed medical air systems. It is sold only as straight 20-foot lengths of hard tubing and measures 1/4 inch to 8 inches in diameter.

Joining Methods

• Depending on the application and the type of copper used, there are several different ways to join copper pieces and fittings together. Soldering and brazing are the two most common methods and use the same flame-joining techniques, save for the fillers. Joints are cleaned with sandpaper to a shiny finish and then coated with flux. The fitting is slipped onto the copper tubing, the pipe is heated and the joints are filled with solder. Brazed joints are used for applications with temperatures as high as 350 degrees. No-flame joining methods include flared joints, roll groove joints, press-connect fittings and push-connect fittings.