Since the first Round Type Reflection Electric Heater of 1928, heaters have been utilized to provide convenient warmth in confined spaces such as household rooms during cold weather. They may also be used to keep pets warm, for plants in a greenhouse, individual workstation warming in a commercial office setting, or even for work crews on construction sites or airport flight lines. There are two primary types of heaters: Central heating units and space heaters.
Central heating has greater reach than space heaters for warming several connected spaces through duct systems, as in a residential unit or commercial building. Heating is controlled through centralized points, such as one wall thermostat per predetermined square footage, where several rooms or an entire building may be temperature-controlled collectively.
Central heating units are powered through a primary heating appliance where the air is warmed. That primary heating appliance is often called a furnace and may be located in a basement or garage, and may consist of a heating element, heat exchangers, a blower to force the heated air into the living space, and a flue to remove toxic gases or fumes derived from the heating process. The heating element may be operated by one of these common forms of energy:
- Water / steam
- Natural gas / propane
Space heaters are used in enclosed rooms or within a limited number of square feet, such as in a bathroom, bedroom, or individual office. Space heaters are generally controlled at the warming unit itself and such temperature control only affects the one unit. They may be powered by one of several different energy sources:
- Mica mineral
- Halogen bulb
- Natural gas / propane
- Kerosene or other oil
- Water / steam
The Center for Disease Control determined that during the period of 1988 to 1994 in the United States, 13.7 million adults used unvented combustion space heaters and 23.1 million adults used electric space heaters. Unvented combustion space heaters were primarily used in rural areas in low income households.
Low-income households are generally the heaviest users of space heaters as the primary method of warming their homes. An estimated 3million low-income households use space heaters as their primary heater and 4 million low-income households use space heaters for secondary heating.
There are many common problems surrounding both central and space heaters. A general risk of fire is present with all types of heaters, primarily electric, gas, propane, oil, and wood or pellet-burning units. Fuel burning heaters offer potential for carbon monoxide poisoning if the heater is leaking, not properly vented, or if the flue is not correctly functioning. The oils used in some heating – such as kerosene or fuel oil – are also often a source of fatal poisoning through ingestion by young children or pets.
Some examples of problems arising from heating unit misuse or space heater defects or malfunction include:
- In Cleveland, Ohio two residents of a basement apartment were found dead by police. The investigation into cause of death resulted in the discovery of fatal levels of carbon within the entire building. Seven additional apartments were vacated to prevent further injury or fatality, after which further investigation led to discovery of a blocked gas furnace flue.
- A 28-year-old woman and her 8-month-old infant were found dead in a friend’s home in Virginia. The gas company found that the gas furnace and two water heaters were improperly vented. Carbon monoxide accumulated in the home and caused both fatalities.
- A 5 year-old boy was killed in Iowa when his family home caught fire while they slept. The cause of the fatal fire was an electric space heater which had been left on without supervision through the night. The heater ignited combustibles and a fire ensued.
- Just before Christmas 1989, a homeowner installed a non-vented outdoor heater inside his home. Without proper venting, carbon monoxide spilled directly into the home, suffocating the man, his pregnant wife and three children.
Heating equipment was the cause of more than 64,000 home fires, 540 deaths, 1400 injuries and $943 million in property damage in 2006. Of these incidences, 73 percent of the deaths were associated with central heating or space heating units. Forty-three percent of the injuries and more than half of the property damage were attributed to central and space heaters. Space heaters are clearly the larger risk among the two common residential heating types and the Consumer Product Safety Commission attributes almost 22,000 of all heating equipment fires in residences and 300 of the deaths to space heaters.
Carbon monoxide poisoning from gas-fueled heaters presents a higher risk of death than fire. Since 1995, there has been an average of 1.8 electrocution deaths per year from electric furnaces. In 2006, heaters accounted for more than 50,000 hospital emergency room visits due to injury.
Defective Heating Systems, Space Heaters and Improper Installation
Several examples of defective central heating systems and space heaters or improper installation include are listed below:
- In February of 2000, Cadet Manufacturing of Vancouver, Washington recalled more than 1.9 million Cadet and Encore brand in-wall electric heaters due to defects resulting in three deaths, two serious burn injuries and property damage claims exceeding $1.2 million, including five house fires. Three hundred twenty of the heaters smoked, sparked, caught fire, emitted flames, or ejected burning particles or molten materials while in operation in consumers’ homes.
- In 1970, a defective Preway space heater was installed by Sears, Roebuck & Company within a family home in Louisiana. The space heater exploded during normal use and seriously injured two family members, at the same time destroying the family home. The family was awarded over $2.25 million in a legal suit against Sears and Preway.
- In 2007, approximately 1.2 million Lasko Ceramic Heaters were recalled by Lasko of West Chester, Pennsylvania, due to faulty overheating cords causing risk of fire. Twenty eight incidences were already reported, with property damage occurring in six of those fires.