Pro Plumbers

Galvanized steel potable water supply and distribution pipes are commonly found with nominal pipe sizes from 3⁄8 inch (9.5 mm) to 2 inches (51 mm). It is rarely used today for new construction residential plumbing. Steel pipe has National Pipe Thread (NPT) standard tapered male threads, which connect with female tapered threads on elbows, tees, couplers, valves, and other fittings. Galvanized steel (often known simply as "galv" or "iron" in the plumbing trade) is relatively expensive, and difficult to work with due to weight and requirement of a pipe threader. It remains in common use for repair of existing "galv" systems and to satisfy building code non-combustibility requirements typically found in hotels, apartment buildings and other commercial applications. It is also extremely durable and resistant to mechanical abuse. Black lacquered steel pipe is the most widely used pipe material for fire sprinklers and natural gas.
It’s impossible to maintain your desired levels of comfort at home or work without the proper plumbing equipment. From hot showers and reliable kitchen appliances to properly flowing sewer lines and leak-free properties, the right plumbing system can keep you from dealing with a heap of plumbing headaches. Leave it to the plumbing professionals to ensure your equipment operates year-round.
I just had my pipe under the sink unclogged  and new pipes put in $600.00, then they flushed out the pipe from under the sink to the outside pipe $700.00, Total of $1.600.00, I thought that the price was high, I got the plumber from Home Advisors, not sure they had to do all they did but they said I needed the work done.  The same evening hike using the dishwasher I had a leak in one of the pipes they put in, they came back the next day to fix it. Don't know if I will use them again.. They were K&D kitchens.

“Don’t assume that every Mr. Fix-it advertising his services in the local Pennysaver or on Craigslist is a licensed plumber,” says one New York plumber. There is no national standard for issuing licenses. Some plumbers are licensed by the state, others by the counties they work in. Check with your local city hall or chamber of commerce. They should be able to direct you to the appropriate source for a list of licensed plumbers in your area.
The word "plumber" dates from the Roman Empire.[3] The Latin for lead is plumbum. Roman roofs used lead in conduits and drain pipes[4] and some were also covered with lead, lead was also used for piping and for making baths.[5] In medieval times anyone who worked with lead was referred to as a plumber as can be seen from an extract of workmen fixing a roof in Westminster Palace and were referred to as plumbers "To Gilbert de Westminster, plumber, working about the roof of the pantry of the little hall, covering it with lead, and about various defects in the roof of the little hall".[6] Thus a person with expertise in working with lead was first known as a Plumbarius which was later shortened to plumber.
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