Wikipedia about Valves
A valve is a device that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure. The word is derived from the Latin valva, the moving part of a door, in turn from volvere, to turn, roll.
The simplest, and very ancient, valve is simply a freely hinged flap which drops to obstruct fluid (gas or liquid) flow in one direction, but is pushed open by flow in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. Modern control valves may regulate pressure or flow downstream and operate on sophisticated automation systems.
Ways to reduce costs associated with the utilization of the water
Professional installation of water meter may take a plumber. It will be able not only to assume, but also seal the counter in such a way that the reading will be error. This will allow precise determination of the amount of water used in the household and issuing the appropriate invoices, that will not in any way overpriced. At the same time plumber will be able to advise the owners of the visited household, how they can reduce the costs associated with the amount of water consumed. At the request will also be able to check whether at home, there is no leakage and no need to replace any seals. Besides a good plumber can recommend the purchase of such sanitary facilities that allow you to save water.
A boiler is a closed vessel in which water or other fluid is heated. The fluid does not necessarily boil. (In North America the term "furnace" is normally used if the purpose is not actually to boil the fluid.) The heated or vaporized fluid exits the boiler for use in various processes or heating applications,12 including water heating, central heating, boiler-based power generation, cooking, and sanitation