How can carbon monoxide enter your home?
Carbon monoxide can escape from any fuel-burning appliance or engine. Some of the common potential sources of carbon monoxide in and around the home include the furnace, water heater, fireplace, woodstove, gas oven or range, unvented kerosene or space heater, grill, generators and other gasoline-powered equipment or engines, propane-fueled equipment such as portable camping stoves, and vehicle exhaust.
Weatherization and efforts to reduce air leakage and create an energy efficient home can reduce fresh air to furnaces and other sources of combustion in the home, leading to increased risks of carbon monoxide build-up.
Chimneys can also be a source of carbon monoxide. Carbon monoxide can spill from vent connections in poorly maintained or blocked chimneys. If the flue liner is cracked or deteriorated, carbon monoxide can seep through the liner and back into the house. If animal nests or other materials restrict or block the flue, carbon monoxide can spill back into the house.
Warming up vehicles in an attached garage, even with the garage door opened, or carport can allow carbon monoxide to enter your home.
Poorly maintained, worn or improperly adjusted combustion devices (such as furnaces) can be significant sources of carbon monoxide. Natural gas should burn in a blue flame with an orange tip. Orange flames without blue can indicate dust and impurities in the air or excess humidity. A yellow flame can mean improper combustion and improper burning of natural gas which can lead to carbon monoxide. Your gas appliance may need maintenance, adjustment or repair by a licensed plumber or contractor. If you smell gas, have symptoms of carbon monoxide or your gas appliance is burning a yellow flame, please call us to report it immediately.
Flues that are improperly sized, blocked, disconnected or leaking can also pull carbon monoxide back into the house from backdrafting. That’s why it is important to have new furnaces and water heaters installed by licensed professionals, as existing chimneys may be the wrong size to allow the furnace to vent properly.
Improperly using fuel-burning devices — such as grills, gasoline-powered tools (lawnmowers, chainsaws, power equipment, generators), camp lanterns and stoves — indoors or in enclosed areas (covered patios, open garages, car ports, boat cabins, trailers or under tents) around the home is a special hazard. Using a gas oven or dryer to heat your home can also risk carbon monoxide build-up.
Clues you can detect that you may have a carbon monoxide problem include:
- Rusting or water streaking on vent or flue pipes, appliance jackets or chimney
- Loose or missing furnace panel
- Streaks of carbon or soot around the vents of fuel-burning appliances
- Debris or soot falling from chimney, fireplace or appliances
- Loose or disconnected vents or chimney, fireplace or appliance
- No draft in your chimney
- Loose, discolored or damaged bricks at the top of your chimney
- Moisture inside of windows or in walls of furnace doors
- An unfamiliar or burning odor
- Decreased hot water supply
- Furnace running continuously or not properly heating the home
- A gas appliance with a yellow-burning flame without blue
Clues you cannot see that you may have a carbon monoxide problem include:
- Internal appliance damage or malfunctioning components
- Improper burner adjustments
- Hidden blockage or damage in chimneys
Only a trained service technician can detect hidden problems and correct these conditions.