Get Carbon Monoxide Alarms
What to do:
Sometimes, the cause of backdrafting is obvious: A vent pipe may be disconnected from a vent hood, for example, or a vent may slope downward. But even a properly installed vent might occasionally backdraft because of high winds or other unusual circumstances. So the surest way to protect your family is to install carbon monoxide alarms. If you don't have CO alarms in your house, go get them today.
Install one on every level, outside sleeping areas, and within 5 ft. to 20 ft. of any sources of CO, such as water heaters, furnaces and fireplaces. If an alarm ever goes off, get out of the house immediately and call the HVAC repair service to correct the problem. The symptoms of CO poisoning are dizziness, headaches and vomiting. If anyone in the house is experiencing these symptoms, leave the house and call the fire department.
Test for proper drafting (top left). Close all the windows and doors and turn on all the bath and kitchen fans. That creates a worst-case scenario for backdrafting. Run some hot water and light an incense stick and see if the smoke is drawn up the vent.
Bad vents cause backdrafing (top right). Water heater vents need to slope upward at least 1/4 in. per foot. The installer responsible for this down-sloping vent apparently didn't know that hot gases rise.
Carbon monoxide alarms save lives (bottom). Every home with an attached garage, fireplace or gas appliances should have carbon monoxide alarms. If you already have them, be sure to test and maintain them according to the manufacturer's instructions.
Plus: Life-Saving Safety Tips for Smoke Alarms