Homes built before the 1960’s were built with galvanized steel piping. This piping has a useful life of 30 to 50 years depending on several variables, such as the mineral content of your municipalities’ water, your home’s water pressure, how the run of pipes in the house are configured, the climate and the quality of material and installation. Galvanized steel is heavy and corrodes, which is why PEX and Copper plumbing has replaced it as the de facto waterline material in residential construction. Copper is light, strong, smooth, safe (plastic piping creates toxic gases when burned), reliable and corrosion-resistant. Copper pipe plumbing is bacteriostatic, which means that bacteria can’t grow in it. Residential Copper pipe comes in two types:
Type L Type L copper pipe has a thicker wall than type M copper pipe making it more durable. Type L is the preferred copper pipe in residential construction. Type L copper pipe is color coded blue, and has BLUE markings along the pipe. Type M Type M copper pipe and tubing can be used in residential plumbing, and often is, because it is less expensive but also lower quality. Type M copper pipe has a shorter useful life than type L copper piping. Type M is color coded with RED markings along the pipe. Type K Type K copper pipe is commercial grade and is usually not used in residential plumbing. Type K is color coded with green markings. Copper pipes are connected by welding pieces together with a propane blow torch. There are two techniques for creating the weld that joins to copper pipes together- Brazing and Soldiering. Soldiering, also called a sweated joint, is typically done for waterlines. Soldier heating temperatures range between 350 and 600 degrees F and uses a tin alloy as the joining material. Brazing is another method of joining copper done at temperatures ranging from 1100 to 1500 degrees F and uses a silver alloy to create the weld. Brazing is used were greater joint strenght is required or where system temperature is as high as 350 degrees. Brazing is commonly used in air-conditioning and refrigeration piping as well as medical gas. Installing Copper plumbing is very much an art. There are five steps to install: Cutting It is important that the copper pipe is cut to exactly the right length so that it reaches the very end of the fitting socket. If the pipe is cut too short it will not make a strong fitting, and if it is cut too long, then it will strain the system. The best way to cut copper pipe is with a tube cutter, it makes a clean square cut. You can also cut copper with a hacksaw, abrasive wheels, or band saws. Take are that the tube is not deformed while being cut. Reaming When cutting copper pipe, rough edges and burrs around the cut are created. Reaming removes these turbulence causing burrs. Excessive turbulence will wear the copper pipe more quickly, and possibly cause a pin whole leak. Cleaning Cleaning is done by wiping the outside of the pipe with emery cloth, and the inside of the pipe with a wire brush. This removes the oxides and any surface debres so that the flux can flow properly during soldering. Oxidation gives copper its wonderful patina color that can be seen on the Statue of Liberty and the roof of Chartres Cathedral. Cleaning will give copper a bright shinny appearance, like a brand new penny. Once cleaned the pipe should not be touche with bare hands. Apply Flux apply a thin layer of soldering paste to the end of each pipe. Use the correct paste flux paste for the type of welding you are doing. Soldering paste should cover about 1” of pipe end. Weld [youtube]http://www.youtube.com/watch?v=07ODV2Bdqow&list=UUX1xI17Mlqbi0jL6xlmIb8Q&index=6&feature=plcp[/youtube] When copper pipes leak, they tend to get pin whole leaks. In most cases pin hole leaks occur near the main water supply running into the house because this is where the water pressure is the greatest in the home. Just like how water cut the Grand Canyon deep into rock, water under pressure also can erode the inside of your piping, burrs from unreamed pipe can accelerate this process.