Abstract: A filter housing assembly for fluid filtration which may be attached to, and removed from, a filter base by a push-actuated release. The filter housing assembly has a top portion with an ingress port and egress port extending therefrom, and a protrusion extending from the filter housing longitudinally axial center. The ingress and egress port are formed in an hourglass shape. A filter key having a base with a groove for mating with said projection, at least one finger extending from said base, and an electronic circuit component housing attached thereto for receiving a printed circuit board, is connected to the filter housing top portion by mating said top portion protrusion with the filter key groove. Both of said ingress and egress port have at least one cavity for the passage of fluid therethrough, where each cavity is exposed in a direction facing away from the printed circuit board.

Abstract: Disclosed is a forced-air heat extractor for use in a conventional fireplace. The heat extractor includes a plenum through which air is circulated by means of a blower which is positioned in an inlet duct connected to the plenum and located in the fireplace. The plenum is provided with a temperature responsive relief closure in its top wall which opens to permit the free flow of heated air upward toward the fireplace's flue in the event the temperature in the plenum exceeds a predetermined value, as might occur in the event of an interruption in the flow of forced air through the plenum, thus protecting the blower motor and associated circuitry from excessive temperatures. A bottom bar having an air inlet to which is coupled the inlet duct is positioned on the forward, lower portion of the fireplace. Upon this bottom bar a firescreen may be conveniently positioned. An outlet duct similarly couples heated air in the plenum to an air outlet in the bottom bar.