Radiator (heating)

Radiators and convectors are heat exchangers designed to transfer thermal energy from one medium to another for the purpose of space heating.

Denison Olmsted of New Haven, Connecticut, appears to have been the earliest person to use the term 'radiator' to mean a heating appliance in an 1834 patent for a stove with a heat exchanger which then radiated heat. In the patent he wrote that his invention was a peculiar kind of apparatus, which I call a radiator. The heating radiator was invented by Franz San Galli in 1855, a Prussian-born Russian businessman living in St. Petersburg. In the late 1800s, companies, such as the American Radiator Company, promoted cast iron radiators over previous fabricated steel designs in order to lower costs and expand the market.

In practice, the term "radiator" refers to any of a number of devices in which a fluid circulates through exposed pipes (often with fins or other means of increasing surface area), notwithstanding that such devices tend to transfer heat mainly by convection and might logically be called convectors.

The term convection heater or convector refers to a class of devices in which the source of heat is not directly exposed. As domestic safety and the supply from water heaters keeps temperatures relatively low, radiation is inefficient in comparison to convection. Convection heaters also work differently to electric radiators in that they disperse heat differently.

The international standard for energy efficient consumer products Energy Star recommends placing heat-resistant reflectors between radiators and exterior walls to help retain heat in a room.

A hot-water radiator consists of a sealed hollow metal container filled with hot water by gravity feed, a pressure pump, or convection. As it gives out heat, the hot water cools and sinks to the bottom of the radiator and is forced out of a pipe at the other end. Anti-hammer devices are often installed to prevent or minimize knocking in hot water radiator pipes.

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Wikipedia