Ranges & Stoves

A stove is an appliance that may be used for heating, cooking or both. Stoves differ from open fires in that they are easier to control, more efficient and may create less pollution. more...

An open fire does not burn efficiently or remove the smoke. Modern stoves burn efficiently and pollute less because they vaporize the fuel thoroughly, mix it with an optimized amount of air, and burn it at optimal temperatures. When heat is extracted, modern stoves often include contraflow heat exchangers so efficient that they condense water from the exhaust.

To maintain efficiencies, modern stoves must be kept clean, including the exhaust flue.

The result of these high efficiencies is that the stove uses less fuel, and emits less pollution while producing the desired amount of heat.

Efficiency

Open fire has three major disadvantages that prompted inventors even in the 16th century to devise improvements: it is dangerous, it produces much smoke, and the heat efficiency is poor. Attempts were made to enclose the fire to make better use of the heat that it generated and thus reduce the wood consumption. A first step was the fire chamber: the fire was enclosed on three sides by brick-and-mortar walls and covered by an iron plate. Only in 1735 did the first design that completely enclosed the fire appear: the Castrol stove of the French architect François Cuvilliés was a masonry construction with several fireholes covered by perforated iron plates. It is also known as a stew stove. Near the end of the 18th century, the design was refined by hanging the pots in holes through the top iron plate, thus improving heat efficiency even more.

In order to prevent air, and therefore smoke, from spilling back into the room a large updraft pulling air (and therefore heat) out of the chimney is needed. This both pulls heat away and pulls air from the rest of the house into the fire and then up the chimney. A fireplace consumes 200 to 600 cubic feet (17 m³) of air per minute, more for a very large fire. Even a mostly closed-off fireplace, for example a modern fireplace with glass doors closed, will use 50-150 cubic feet per minute. High airflow creates a draft which pulls heated air out of the house to be replaced with cold air leaking in from the outside. Second, in an open fire some of the combustible gas coming off the wood escapes and thus does not ignite and is lost. By controlling the inflow of air to allow only what a fire needs to burn, modern stoves can reduce the consumption of air to as little as 15-30 cubic feet per minute, though consumption varies.

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