Kerosene heater
A kerosene heater, also known as a paraffin heater, is a portable, unvented, kerosene-fueled, space-heating device. In the United States they are used mainly for supplemental heat or as a source of emergency heat during a power outage.[1] In some countries, particularly in Japan, they are used as the primary source of home heat. Most kerosene heaters produce between 3.3 and 6.8 kW (11000 to 23000 BTU per hour).
Operation
A kerosene heater operates much like a large kerosene lamp. A circular wick made from fiberglass is integrated into a burner unit mounted above a font (tank) filled with 1-K kerosene. The wick draws kerosene from the tank via capillary action. Once lit, the wick emits flames into the burner unit which heats air via convection or nearby objects via radiation. The burner is designed to properly oxygenate and distribute the flames. The flame height is controlled by raising or lowering the exposed wick height inside the burner unit via an adjusting mechanism. The kerosene heater is extinguished by fully retracting the wick into a cavity below the burner, which will snuff out the flame.
There has been a technological advance in kerosene heaters, some now use electricity to power a fan to force the heated air out, making it possible to heat up rooms faster. There is also thermostat controlled operation installed in modern kerosene heaters as well. However most kerosene heaters require no electricity to operate. Most heaters contain a battery-operated or piezo-electric ignitor to light the heater without the need for matches. If the ignitor should fail the heater can still be started manually.
The wick requires routine maintenance. Usually the kerosene heater is placed outdoors and allowed to operate until it runs out of fuel. Tar and other leftover deposits on the wick are burned off. The wick will eventually deteriorate to the point where it will need to be replaced.
Details of Operation
A kerosene heater is an appliance in which kerosene is gasified by surface evaporation and burned. The amount of kerosene evaporated and heat generated can be increased in direct proportion to the area of the contact surface between the kerosene and air. The wick used in a kerosene heater consists of many bundles of fine fibers and, in accordance with the principle behind it, it is designed to provide a large evaporation area. A wick consists of bundles of thin fibers and countless capillary tubes. The kerosene is drawn up from the tank into the combustion area by these capillary tubes. As a result, if the kerosene becomes viscous or dirt and dust find their way inside the heater, the capillary tubes will become clogged. This will cause a deterioration in the drawing of the kerosene and combustion will no longer be possible.[2]
Odors of Operation
When filling a kerosene heater, there is an opportunity for the fuel to vaporize and create an odor in the air. This is why it is important to fill the heater in a garage or outdoors. When a kerosene heater is first ignited, it takes a few seconds to a few minutes for the fuel to mix with the air in the perfect ratio for complete combustion. For that space of time, the fuel to air mixture is quite rich. This results in a small amount of unburned kerosene. Once the heater is burning normally, no additional odor is created. An improperly adjusted wick causes smoke and odor.[3] This is corrected by adjusting the wick-height. A wick with carbon build-up will also cause odor. A wick in this condition should be replaced. Odor may also be apparent when the heater is extinguished. The wick holder remains quite warm. When lowered, the wick continues to draw kerosene, causing a vaporization of the fuel which is detected as odor.
Safety Hazards
Because kerosene heaters are usually unvented, all combustion products are released into the indoor air. Among these are low levels of nitrogen dioxide and carbon monoxide.[4] An improperly adjusted, fueled, or poorly maintained kerosene heater will release more pollutants, particularly through incomplete combustion. Use of a kerosene heater in an improperly ventilated home, especially those that are modernly well insulated, could pose a health risk. Most manufacturers recommend that a window or door be left cracked open. Kerosene heaters should not be left unattended, especially when sleeping. A kerosene heater, as any heater that uses organic fuel, when running out of oxygen can produce massive amounts of soot and carbon monoxide.[5] Failure to follow these precautions could result in asphyxiation or carbon monoxide poisoning.
Hot surfaces on the heater pose a fire and burn risk. The open flame poses an explosion risk in environments where flammable vapors may be present, such as in a garage. Use of improper or contaminated fuel could cause poor performance, a fire or an explosion. There are the usual risks involved with the storage of kerosene and when refilling the heater.
Always use clear 1-K Kerosene. Use of impure fuel can cause extra soot. A risk of explosion is present with even trace amounts of gasoline mixed in the fuel, which is why it is illegal in many jurisdictions to dispense gasoline into unauthorized containers such as kerosene jugs; be sure to store in a container that has not been used with gasoline.[6]