What most people know about carbon monoxide is that it is a deadly gas that can exist in your home, and practicing carbon monoxide safety by having a carbon monoxide detector in your home is a good idea. One Hour Heating & Air Conditioning® of Charlotte, North Carolina we feel it is important that our customers know more about the risk of carbon monoxide gas in your home, understand where it comes from, and how to reduce the risk of exposure to carbon monoxide poisoning for your family.


Carbon monoxide (CO) is an invisible, odorless gas by-product of flame combustion. In more simple terms, CO is produced whenever a material burns. Appliances that use natural gas, propane gas, or oil as a fuel all use a controlled burn to heat. Furnaces, water heaters, and space heaters are common examples. There are simple ways to prevent carbon monoxide exposure in the home, however, the Center for Disease Control estimates that approximately 400 people in the United States die every year from accidental CO poisoning. Unintentional CO poisoning also causes an estimated 21,000 people to visit an emergency room every year. For many the result is a mild case of nausea, vomiting, dizziness, headache, fatigue, and chest pain. But about 10% of these people have to be hospitalized for treatment of more serious problems of respiratory illness and brain damage.


The most common sources of carbon monoxide poisoning in homes are the use of gasoline powered generators and malfunctioning furnaces and stoves. Gas powered generators should never be run inside the home! Don’t be lazy, and don’t think you can just crack open a window or door and it will be fine. It won’t. Keep the generators outside.
Preventing carbon monoxide exposure from furnaces and appliances primarily comes down to maintenance. A properly maintained gas or oil fired furnace is designed to burn the fuel with a very high efficiency that produces carbon monoxide as a byproduct of the burnt gases. That carbon monoxide is vented through the flue system and dispersed to the outside air where it becomes so diluted that it will do no harm.


The Consumer Product Safety Commission (CPSC) recommends having at least one carbon monoxide detector in each home, preferably near the bedrooms. Having one on every level and in every bedroom, is even better. Carbon monoxide detectors are a very important safety element for your home. But since carbon monoxide is colorless and odorless, when the detector alarm goes off, the CO is already in the air. When carbon monoxide is present in the air we breathe, it rapidly enters the bloodstream and begins causing problems. Avoidance through preventive maintenance on heating and air conditioning system and your appliances lowers your risk of exposure significantly.

Regular maintenance on your heating and cooling system along with any gas or oil fired appliances is the most effective carbon monoxide safety measure you can take to prevent carbon monoxide exposure in your home. Not only does this save you a lot of money (regular maintenance costs a lot less than repairs), but qualified technicians will be able to detect impending issues that could lead to CO contamination inside your home.

A good maintenance tune up of your furnace should include a Furnace Safety Check by a qualified technician. Furnace maintenance by your HAVC technician should include checking and adjusting gas pressure to ensure an efficient burn, checking the ignition system, cleaning sensors, and checking the draft inducer assembly to ensure proper venting of burnt gases.

At One Hour Heating & Air Conditioning® of Charlotte we provide a comprehensive furnace safety check that also checks the following components that can affect carbon monoxide exposure:

  • Heat exchanger is inspected for cracks, leaks, efficiency, and overall condition
  • Gas and oil connections are checked for leaks and seal integrity
  • Ignition system is checked for proper function
  • Gas pressure is adjusted for efficiency
  • Carbon Monoxide detector is checked
  • Burner crossover ports are checked for leaks and overall condition
  • Combustion intake and exhaust piping is checked for integrity, flow, and leaks
  • Flue piping is checked
  • Draft inducer assembly is checked for integrity, flow, and leaks


The purpose of furnace tune ups and safety checks is to make sure the individual systems of a furnace are each working correctly, and they are all working together as designed. For example, incomplete combustion is a common problem that not only lowers efficiency, but it increases the amount of carbon monoxide being produced. Poor combustion can also produce lower temperatures in the combustion chamber which can then affect air flow, or draft, through the flue. There you have two systems, the efficiency of one dependent on the other.

Flue systems have their own function that can affect carbon monoxide exposure risk as well. Leaks in a flue system can allow exhausted gases to leak into attics, basements, and even living spaces. The function of an inadequate flue system can be susceptible to backdraft of gases by extreme temperature changes or heavy winds. These conditions can cause changes in air pressure inside your home. Even small changes, not enough for you to notice, can affect the movement of air in and around your house that can vacuum exhausted gases into the structure.

A qualified HVAC technician can identify any existing conditions that might lead to this problem and run more extensive tests that measure CO in the flue pipe, and whether or not the gases are exiting the flue pipe properly.


Professional regular maintenance is key to preventing carbon monoxide exposure. But you can also check around your HVAC system and your home for some telltale signs of possible CO risks. If you see any of these conditions, be sure to call for tune up and safety check. The qualified technicians at One Hour Heating and Air can come to your home any day of the week.

  • Streaks of soot around fuel-burning appliances, or fallen soot in a fireplace
  • Absence of an upward draft in your chimney
  • Excess moisture and condensation on windows, walls and cold surfaces
  • Rusting on flue pipes or appliance jacks
  • Orange or yellow flame in combustion appliances (the flame should be blue)
  • Damaged or discolored bricks at the top of the chimney


Carbon monoxide is referred to as a “silent killer” for a couple reasons. We already explained that it is odorless and colorless, so you can’t see it or smell it. The reason is because the physical symptoms you will feel are very similar to catching the flu. People often make this assumption and ignore the symptoms, or treat them improperly.
The first symptoms will usually include a mild headache and being short of breath with even moderate exercise. With continued exposure, the symptoms will escalate headaches, dizziness, fatigue and nausea. If not addressed the symptoms will progress to confusion, impaired judgement and coordination, and eventually loss of consciousness.


  • You feel better when you are away from home
  • Everyone is the home is sick at the same time (the flu virus usually spreads from person to person)
  • The family members most effected spend the most time in the house
  • Indoor pets appear ill
  • You don’t have a fever or body aches, and you don’t have swollen lymph nodes that are common with the flu and some other infections
  • Symptoms appear or seem to get worse when using fuel-burning equipment


North Carolina is among 38 other states that require carbon monoxide detectors in private dwellings that have fossil-fuel burning devices (gas or oil fired furnaces, water heaters, dryers, etc.) or attached garages. This is a law that helps us simply do the right thing to protect our families. The minimum recommendation is to have at least one detector on every level of the home, and preferably in or near sleeping areas. The best method is to have detectors in every living area, kitchen area, and in each bedroom. It’s also important to follow the manufacturer instructions for installation and testing, and to replace the battery twice per year.

The average lifespan of a carbon monoxide detector is between 5 to 7 years. This can vary by manufacturer, so be sure to check the product packaging or the manufacturer for a recommended replacement date. Making sure you know the details of your homes carbon monoxide detector, is one of the most important components of carbon monoxide safety!


If your home carbon monoxide detector goes off, leave the building and make sure everyone is out. Don’t ignore it or just open windows to air the home out. Even if everyone feels fine you need to have the utility company or a qualified HVAC technician to identify the source of the problem.

The bottom line on preventing carbon monoxide poisoning is to install CO detectors and have your HVAC, water heaters, and other appliances checked and maintained on a regular basis. Do that and you can live in comfort, efficiency, and not in fear of carbon monoxide.


  • Do have your heating system, water heater and any other gas, oil, or coal burning appliances serviced by a qualified technician every year.
  • Do install a battery-operated or battery back-up CO detector in your home and check or replace the battery when you change the time on your clocks each spring and fall.
  • If the detector sounds leave your home immediately and call 911.
  • Do seek prompt medical attention if you suspect CO poisoning and are feeling dizzy, light-headed, or nauseated.
  • Don’t use a generator, charcoal grill, camp stove, or other gasoline or charcoal-burning device inside your home, basement, or garage or near a window.
  • Don’t run a car or truck inside a garage attached to your house, even if you leave the door open.
  • Don’t burn anything in a stove or fireplace that isn’t vented.
  • Don’t heat your house with a gas oven.
  • Don’t use a generator, pressure washer, or any gasoline-powered engine less than 20 feet from any window, door, or vent.

One Hour Heating & Air Conditioning® of Charlotte wants to help you practice carbon monoxide safety. Give us a call today!