A pilot light is a small flame that is kept lit to provide a catalyst for a much larger flame when it is called upon to do so. These lights are common in home appliances that use natural gas or petroleum, such as central heating furnaces, water heaters and even older stoves. They are also found on hot air balloons.
The way that a pilot light usually works is by maintaining a permanent flame at a very low level. It may glow blue in many cases. As more fuel is added to the mixture, the flame will ignite other burners and create a fire capable of doing a specific job, such as heating water or air, or cooking. Even once those burners are turned off, the pilot remains on.
Although this flame is meant to stay on a majority of the time, there may be times when it is extinguished, either on purpose or accident. While reigniting a pilot is not a big ordeal, careful attention should be taken to light it exactly as specified in the directions. Otherwise, it could become dangerous.
In the summer months, when a gas furnace is no longer being used, some people may choose to shut down the pilot light. This is a personal choice and will obviously save some money on the consumption of natural gas or other types of fuel used for the furnace. There is usually a valve that will squelch the fuel to the flame, effectively extinguishing it. Given that some estimates say the fuel consumption by the pilot can represent 50% of the appliance’s fuel consumption, extinguishing the flame may be good way to save some money during long periods of dormancy.
A pilot light will ensure the functionality of a natural gas appliance such as a water heater or gas range even if the electricity goes out. Some gas appliances are moving away from the use of these flames, however, and they now depend on electrical ignition. They may still be able to be lit with a match if electricity is unavailable, but this is generally not advisable.
If the flame does get extinguished accidentally, there are safety features included on appliances that should stop the flow of natural gas as well. A thermocouple will sense that the flame is no longer lit and take appropriate actions by automatically shutting a valve, even if no electricity is available. If the gas were allowed to continue into the system without being burned, it could easily fill the room or home, causing a risk of explosion or asphyxiation to any inhabitants.
