Central heating
A central heating system provides warmth to the whole interior of a building (or portion of a building) from one point to multiple rooms. When combined with other systems in order to control the building climate, the whole system may be an HVAC (heating, ventilation and air conditioning) system.
Central heating differs from space heating in that the heat generation occurs in one place, such as a furnace room in a house or a mechanical room in a large building (though not necessarily at the "central" geometric point). The heat is distributed throughout the building, typically by forced-air through ductwork, by water circulating through pipes, or by steam fed through pipes.
The most common method of heat generation involves the combustion of fossil fuel in a furnace or boiler. Increasingly, buildings utilize solar-powered heat sources, in which case the distribution system normally uses water circulation.
In much of the temperate climate zone, most new housing has come with central heating installed since the Second World War, at least. Such areas normally use gas heaters, district heating, or a oil-fired system, often using forced-air systems. Steam-heating systems, fired by coal, oil or gas, are also used, primarily for larger buildings. Electrical heating systems occur less commonly and are practical only with low-cost electricity or when ground source heat pumps are used. Considering the combined system of central generating plant and electric resistance heating, the overall efficiency will be less than for direct use of fossil fuel for space heating.
Źródło: https://en.wikipedia.org/wiki/Central_heating
Who the best plumbers to check?
Is every plumber will be able to adequately take care of our problem? Everyone knows perfectly well that in all areas occur are bad professionals who, instead of repairs endow us with extra costs and inconvenience. To avoid such situations, it is always worth to choose the best plumbers, who have years of experience and the necessary skills, users can quickly and efficiently get rid of the problem. How can you find them? Ideally, of course, to suggest that the opinions of friends people have had the opportunity to try out these services in their own homes. If you do not have such capabilities, is always worth a bet on companies that operate on the market the longest.
Drain cleaner - chemical
Chemical drain cleaners can be in solid or liquid form that are readily available through hardware stores, though some (primarily acidic ones) are intended for use by licensed plumbers.1
Alkaline drain openers
Bottles of alkaline drain cleaners containing sodium hydroxide can dissolve greases and hair.
Alkaline drain openers primarily contain sodium hydroxide and some may contain potassium hydroxide. They may appear in liquid or solid form.
Liquid formulations of corrosive alkaline drain cleaners can contain sodium hypochlorite (bleach) and lye (sodium hydroxide or potassium hydroxide) in concentrations up to 50 percent. Other corrosive mixtures come as two-part cleaners that are mixed as they are poured in the drain opening. Inside the drain the two solutions react to release a gas, and surfactants trap the gas as dense foam. The intent of this foaming action is to coat the inside of the drain pipe to dislodge more of the substances that form the clog.
Solid formulations of corrosive alkaline drain cleaners in the form of sodium hydroxide or potassium hydroxide granules can provide more concentrated effective ingredients. Some patented, solid-formula cleaners add aluminum turnings that react with the solid hydroxide in water to heat the caustic mixture to a boil.
Alkaline drain openers can dissolve hair (containing proteins) and fats inside pipes via alkaline hydrolysis of amide and ester respectively:
RCONH2(amide or proteins)+ OH? ? NH3 + RCOO?
RCO2R?(ester or fats)+ OH? ? R'OH + RCOO?
Źródło: https://en.wikipedia.org/wiki/Drain_cleaner