Some Wikipedia facts
The word "plumber" dates from the Roman Empire. The Latin for lead is plumbum. Roman roofs used lead in conduits and drain pipes and some were also covered with lead, lead was also used for piping and for making baths. 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". Thus a person with expertise in working with lead was first known as a Plumbarius which was later shortened to plumber.
A plumber is a tradesperson who specializes in installing and maintaining systems used for potable (drinking) water, sewage and drainage in plumbing systems. The term dates from ancient times, and is related to the Latin word for lead, "plumbum".
Źródło: https://en.wikipedia.org/wiki/Plumber
Boiler - what is it?
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.
Źródło: https://en.wikipedia.org/wiki/Boiler
Mounting tap operated on photocell
Useful plumbing services allow us to find good ways to reduce water bills. One such method is the installation of automatic flushing, which itself will launch its tank with water after using the toilet by us and cums the amount of water that is provided. We can also be mounted in the bathroom faucet supported on a photocell, from which the water will be flying only when the photocell registers the execution of movements with your hands. As a result, no longer a situation occurred that the tap water will bleed, but for a long time no one in the bathroom. Plumber can also refer us to other methods allowing to save water, which is much cheaper than installation of these devices, and can be equally effective.