You turned on your central heater and now your house smells like my brother's socks. And you don't know what to do about it. First make sure that any ducting under the floor is not touching the ground and that it is well insulated. Ground water and water vapors are banquet time for mildew and other fungi. Next, remove the furnace filters and turn the fan on. Make sure the burners aren't on, just the fan. Next, fill a spray bottle with good old-fashioned household bleach -- add a little cologne or a fragrance to the liquid, if you like -- and spray the concoction into the furnace. The fan will force the sweet-smelling disinfectant solution throughout the ducting, kill mildew, fungi and bacteria and leave your home as fresh and sweet as a Carey brother's personality. And that's the On The House tip for today.