Abstract: In accordance with the principals of the present invention, a furnace unit adapted to be installed in-line with a fuel source of a furnace modulates natural gas or propane to reduce fuel consumption, minimize temperature overshoot, and reduce furnace short cycling. A modulator is contained with the furnace unit. The modulator is in gaseous communication with the in-line gas fuel source. A furnace sensor senses furnace criteria related to the operation of the furnace. A microcontroller receives from the furnace sensor furnace criteria and controls the modulator based on the furnace criteria. In a further aspect of the invention, an environmental sensor can be provided to sense environmental criteria related to the operation of the furnace. In a further aspect of the invention, a base unit in electrical communication with the furnace unit can be provided, the base unit determining energy consumption usage and savings.

Abstract: In accordance with the principals of the present invention, a furnace unit adapted to be installed in-line with a fuel source of a furnace modulates natural gas or propane to reduce fuel consumption, minimize temperature overshoot, and reduce furnace short cycling. A modulator is contained with the furnace unit. The modulator is in gaseous communication with the in-line gas fuel source. A furnace sensor senses furnace criteria related to the operation of the furnace. A microcontroller receives from the furnace sensor furnace criteria and controls the modulator based on the furnace criteria. In a further aspect of the invention, an environmental sensor can be provided to sense environmental criteria related to the operation of the furnace. In a further aspect of the invention, a base unit in electrical communication with the furnace unit can be provided, the base unit determining energy consumption usage and savings.