Leonard Base, of Kingman, Kan., figures he cut more than 60% off his heat bill last winter with a simple device that captures "waste heat" in the chimney and blows it back into the house.

His new chimney heat saver consists of a length of 4-in. pipe formed in a U-shape and slipped 13 ft. down into the chimney. A fan outside the chimney blows air down into the pipe, which reaches almost to the fireplace, and back up the other side.

"The device not only reclaims much of the heat leaving the house through the chimney, but by forcing air into the house, it also pressurizes the house so that cold air isn't drawn into the house through cracks, crevices and other openings," says Base.

Base used automobile exhaust pipe to build the prototype he's had operating in his house for the past three years and has now patented. The Base family has used a standard fireplace to heat their 2,300 sq. ft. home since installing the heat saver. They run their electric furnace only at night.

The device uses a small 5-in. dia. fan to move the air down through the chimney and back up before going through more than 20 ft. of pipe to an inlet into the house. Base says the air could enter the house anywhere in one or more locations. The small fan, he says, moves more than enough air for the system.

The chimney on the Base house is 12 in. square on the outside. Base says the device would work on smaller or larger chimneys by adapting size of the pipe to size of the chimney opening.

Key to the success of the device is the amount of heat escaping up the chimney. "Even with a small fire in the fireplace, very warm air blows into the house from the system." notes Base. "Any gas, oil, or wood furnace or stove that is losing warm air up the chimney could benefit."