It's widely known that carbon monoxide and nitrogen dioxide detectors should be installed in homes that have fuel-burning furnaces, but it's a good idea to understand why. If you are a homeowner who has a furnace in your house that uses fuel, it's important for you to understand how these dangerous gases form and the health risks they pose to you and your family members. Here's what you need to know.
Stoichiometry of Combustion
Stoichiometry (stoy-key-ah-mah-tree) is the relationship between the amounts of various substances that take part in the process of a reaction or form a compound. Regarding stoichiometry in a fuel-burning furnace, complete combustion calls for the perfect mixture of fuel and oxygen, both in correct amounts and combined chemically in order for both to be completely consumed. This would mean nothing would be left behind.
But since the world is not perfect, it's difficult to always get the amounts correct and combined perfectly in order for the combustion of the fuel source to be entirely complete and the oxygen in the air to be entirely combined. If there is not enough oxygen present, the fuel source cannot burn completely, resulting in incomplete combustion of the compounds that are formed during the combustion process. Carbon monoxide and nitrogen dioxide are two of those compounds.
Stoichiometry is the same scientific process that allows you to snuff out the flame of a candle in a jar by putting a lid on the jar. When you remove the oxygen source, the flame goes out due to this phenomenon known as stoichiometry of combustion. When this happens in your furnace, the incomplete combustion of the fuel forms dangerous gases.
Carbon Monoxide & Nitrogen Dioxide
Carbon monoxide is deadly, mostly because it is undetectable to human senses. People don't know they are being poisoned by carbon monoxide while it is happening. Nitrogen dioxide is also deadly, but it can be detected by human senses because it has a rusty color and has a pungent odor. Due to these gases being dangerous, there are detection devices available for homes and businesses.
Detectors can operate on batteries or be hard-wired directly into the building's electrical circuitry. Battery-operated detectors need to have their batteries replaced regularly, which most homeowners do at the same time they replace batteries in their smoke detectors. Detectors that are hard-wired should have a battery back-up system in case the power goes out.
Causes of Incomplete Combustion in Furnaces
Now that you understand the process of combustion and how these dangerous gases are formed, it's important to be able to identify what types of problems can cause the combustion process to be incomplete. That way, you can make sure your furnace is in good working condition so the risk of an incomplete combustion is reduced. Since oxygen is crucial in the combustion process of fuel, it is important that all flues and vents are in the open position during combustion.
The flue is necessary to allow dangerous gases to escape from the furnace. When it is blocked or closed, the gases cannot escape safely through the flue, which is usually found in the chimney. But it can also prevent fresh air from moving into the vent of the furnace, which causes incomplete combustion. Fresh air can only enter into space when stale air (and gases) are removed from the space.
It's also important that air filters are cleaned or replaced regularly so the flow of air is not blocked. When you clean or replace the air filter on your furnace, make a note of it on the calendar as a reminder and follow the guidelines from the manufacturer.