1. Test your garage door opener monthly to ensure that it reverses when it hits an obstruction or when its sensor beam is interrupted. 2. Vacuum the clothes dryer's exhaust duct at least once a year. If the duct is plastic, replace it (it's a fire hazard). Rigid sheet-metal ducting is best. 3. Replace furnace filters quarterly, or as recommended by the furnace manufacturer. 4. Test all...