Central heating

A central heating system heats a building from one main source of heat. There may also be ventilation, and air conditioning  which can cool the building. 

A central heating system has a furnace or boiler that uses fuel or electricity to heat water or air. Heated air is pumped through ducts. Steam  or hot water is pumped to radiators.  The fuel may be coal or wood, oil, kerosene, natural gas, or electricity.

Central heating gives better temperature control in a building.. Large buildings may be divided into smaller parts  with their own temperature controls. 

Before the general use of central heating in most homes there would be a fire in one room and the whole family would be there in the evening.  With central heating people can use the different parts of the house.  In 1965 a British Gas advertisement said  that central heating “turns bedrooms into playrooms”.

 Overview 
In much of the temperate climate zone, central heating started to be fitted since before the Second World War. Coal-fired steam or hot water systems were common.  More recently fuel oil or gas has been used more.  Electrical heating systems are generally more expensive.   Heat pumps are now being installed as they are cheaper and produce less   greenhouse gas.  .

Some buildings have central solar heating usually connected to radiators.   Gas heaters and district heating are other possibilities.  District heating uses waste heat. It need underground piping to circulate hot water or steam.

 History 
In ancient Korea, Greece and Rome some buildings had under-floor heating. This system is called a hypocaust.    Some later monasteries had them. They were also used in the Byzantine and Ottoman Empires and in the Baltic region.

References

Category:Heat transfer
Category:Housing