Carbon monoxide is often referred to as the silent killer since it contributes to hundreds of deaths in the United States alone each year. It also sends thousands of people to the emergency room and forces many of these people to be hospitalized. The main concern with carbon monoxide is that it is completely colorless and odorless, which means the only way to know it’s present is if you have carbon monoxide detectors in your house. We’ll explain the role some HVAC systems can play in releasing carbon monoxide into a house and discuss all the locations in a home where you should have carbon monoxide detectors installed.
How an HVAC System Can Lead to Carbon Monoxide Issues
The first thing to note is that not all HVAC systems can produce carbon monoxide and not every home requires carbon monoxide detectors. If you have an all-electric home with a heat pump, electric water heater and no gas-burning appliances like a stove or oven, you generally don’t need any carbon monoxide detectors. In this case, there is nothing in your house that could potentially produce carbon monoxide. The exception is if you have any type of propane or wood-burning stove like a fireplace or pellet stove since both propane and wood can also produce carbon monoxide when they burn.
If you have a gas furnace or any other gas-burning appliance, such as a water heater, you need to make sure you have carbon monoxide detectors in various parts of your house. Furnaces and other gas appliances don’t always produce carbon monoxide since natural gas normally burns cleanly. As long as the gas fully combusts, it produces a bright blue flame and the only byproducts are water vapor and carbon dioxide. When the gas doesn’t combust fully, you get weak yellow or orange flames that aren’t nearly as hot and can produce carbon monoxide as a byproduct.
In a furnace, incomplete combustion that can produce carbon monoxide usually happens due to one of two issues. The first is that there isn’t sufficient oxygen being drawn into the furnace, which essentially starves the flames and prevents the gas from fully combusting and burning cleanly. You can also end up having issues with incomplete combustion if the furnace burners are overly dirty due to a lack of regular maintenance.
This second issue is much more common nowadays. That’s because all modern furnaces have an inducer fan that continually pulls air into the combustion chamber to ensure the flames aren’t starved of oxygen. The inducer in a conventional furnace just draws in air from the area around the unit. In a condensing furnace, you have an air intake pipe that sticks out of the house so that the inducer pulls air in from outside.
Every draft-induced furnace also has a safety mechanism known as a pressure switch. When the furnace turns on, the inducer fan is the first thing that comes on. The pressure it creates by drawing air into the furnace and up activates the pressure switch, which in turn activates the gas valve so that the burners can light. If the inducer isn’t pulling in enough air, and the exhaust fumes aren’t getting drawn out of the combustion chamber, there won’t be sufficient pressure to activate the pressure switch. That means the gas won’t ever come on, and the furnace won’t light. If the pressure ever drops while the furnace is lit, the pressure switch will also close and cause the furnace to shut off.
Where in a House Should You Install Carbon Monoxide Detectors?
There are very specific building code requirements that stipulate where you’re legally required to have carbon monoxide detectors. These requirements apply only when building a new house or renovating a substantial portion of an existing one. Nonetheless, they are good rules for all homes with any type of gas appliance.
The first rule is to place one carbon monoxide detector approximately 15 feet away from a gas furnace and every other gas appliance in the house. In many homes that have both a gas furnace and a water heater, the two units are located side by side or at least fairly close together. In this case, a single detector will suffice for both units. You generally don’t want the detector any closer than 15 feet since this can lead to false alarms frequently occurring when the furnace or water heater first lights.
You’re also supposed to have one detector on every floor of your house. Unless your furnace is in the attic, garage or crawl space, the detector near it will suffice for your basement or whichever floor the furnace is located on. While one detector per floor is the minimum code requirement, many experts recommend larger homes have at least two detectors per floor. In this case, it’s best if each one is on the opposite side of the house from the other to cover a greater area.
The most important place for carbon monoxide detectors is in or near each of your bedrooms. If you’re placing the detectors out in the hall that leads to your bedrooms, you need to make sure you have one within 10 feet of each bedroom door. In many cases, that means that you can have one detector that covers multiple bedrooms. Having detectors near your bedrooms is so important because the majority of cases of fatal carbon monoxide poisoning occur at night when everyone in the household is asleep and can’t recognize the symptoms of carbon monoxide exposure.
All your carbon monoxide detectors should also be mounted on the ceiling or a wall. If mounting a unit on the wall, make sure it is at least 5 feet above the floor. The reason is that carbon monoxide is slightly lighter than air. While it eventually gets evenly distributed in the air throughout an entire space, it still rises slightly at first. That means your detectors will typically go off slightly sooner if you have them higher up on the wall or the ceiling.
The Importance of Testing Your Carbon Monoxide Detectors
Any carbon monoxide detector has the potential to suddenly stop working. That’s why you should make it a habit to go around your house every month and test each of the detectors. If the detector is working, the alarm should immediately sound when you press the test button. If you have a battery-powered unit that doesn’t go off when you test it, replace the batteries and try again. If it still doesn’t work, replace it immediately. Carbon monoxide detectors generally last for only five to seven years. That means you need to make note of when you installed them and don’t wait any longer than seven years before replacing them.
When installing carbon monoxide detectors, you have the choice between battery-powered and hard-wired units. Battery-powered units are less expensive since you need to hire an electrician to connect hard-wired units to your electrical system. Nonetheless, hard-wired detectors are the safer choice since almost all of them also have batteries that serve as a backup in case your power goes out. The other reason is that all the detectors in the house are interconnected, so they will all go off instantly if any one of them detects carbon monoxide. This means you’ll immediately be alerted to the presence of carbon monoxide in your house no matter which room you’re in.
The best way to ensure your HVAC system doesn’t ever contribute to carbon monoxide issues is with regular inspections and maintenance. As one of the Las Vegas area’s most trusted HVAC companies, Polar Air & Heating, Inc. is here to expertly handle your heating and air conditioning maintenance needs as well as indoor air quality. We service every make and model of HVAC equipment and are also the company to turn to if you need repairs or a new installation.
For more information on the importance of getting your HVAC maintained this fall, contact us at Polar Air & Heating, Inc. today.
