All combustion appliances that draw air from inside the building present potential hazards. These include water heaters, furnaces and ranges. The safest and simplest solution is to install “sealed” combustion appliances that draw air from outside the house. These units get all the air used for combustion and draft from the outside. There should be no opportunity for flue gases to enter the building. A wide selection of sealed combustion furnaces and water heaters is available.

Unfortunately, sealed combustion gas ranges are not available. A properly operating gas range with an exhausting range hood (200 cfm minimum) shouldn’t cause a problem. However, over time the burners may become dirty and produce more harmful gases. Plus, the occupants may not operate the exhaust fan every time they turn on the range or oven. These factors make the use of a gas range risky.