Fires and Appliance Safety
December 28, 2016 Leave a comment
The weather has definitely gotten colder and heating systems are being put to the test. There are different kinds of systems; electric resistance, gas-fired forced air, hot water, and steam to name a few. Regardless of the type of system, the potential for accidental fire is part of all heating systems. During this time of year, it not uncommon for problems to develop which, when left unattended, can result in significant damage to homes and businesses. For example, furnaces, both gas and electric, should be cleaned at least once per year; at the beginning of the heating season. Some people think that just because they change their air filters every once-in-awhile maintenance is complete. NOT SO! Depending on the efficiency of the filter in use, some dust particles will pass through the filter media and accumulate on blower blades, motors, and heat exchanger surfaces. The burning smell often detected when the furnace is first started is the result of dust accumulation. If the furnace is never cleaned, dust accumulation can ignite and spread outside of ductwork. Similarly, if the controls area is never cleaned, burners can become clogged resulting in poor combustion and sometimes, delayed ignition. Delayed ignition of gas/air mixtures can become explosive and when ignited, can release a tremendous amount of heat with deadly force. Poor combustion can also produce carbon monoxide which when inhaled can be deadly, especially to elderly people and young children with respiratory problems. Similarly, electric heating systems such as heat pumps should be checked for proper operation as well as components that are in good working condition. One of the biggest problems that should be guarded against is the wiring insulation that becomes brittle with age and cracks. Exposure of conductors can result in short circuiting leading to a fire which can then spread to the structure. Just because a circuit is protected with a circuit breaker doesn’t mean that a fire can never develop. Circuit breakers are current limiting devices NOT thermal limiting devices. Heat exchange coils, motor, fans, and blowers in heat pumps should also be kept clean. Heat pumps come in different configurations such as air to air, air to water, and air to ground. In the last two configurations, a fluid such as water or glycol is circulated to transfer heat to or from the heat pump. In order to do so, a pump is used to circulate the fluid and must also be serviced at certain times. Failure to do so can result in pump motor burnouts that could result in fire. Remember, the pump and its motor are usually two separate components unless intentionally manufactured as a single unit. Lastly, there is not much that can be done with hot and steam boilers except to make sure that the wiring is in good condition, stack temperature is not excessive, and piping is also in good condition. Also, remember that piping can also be a source of ignition. Hot piping can ignite combustibles if contact is maintained long enough. Maintenance is the key to preventing fires in heating equipment.
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