Abstract: A coupling to connect a primary heat exchanger to a condensing heat exchanger of a furnace includes a coupling box extending between a primary heat exchanger and a condensing heat exchanger. The coupling box defines a flow path for flue gas between a primary heat exchanger outlet and a condensing heat exchanger inlet. A tube sheet is located at a distance from the tube sheet in the coupling box. The liner and the tube sheet define an insulating liner space therebetween reducing condensation on the liner.

Abstract: An inducer fan assembly including an inducer fan housing having a flue vent connection member configured and disposed to be connected to an exhaust gas flue vent. The flue vent connection member includes a flue gas outlet and a flue vent condensate inlet.

Abstract: A coupling to connect a primary heat exchanger to a condensing heat exchanger of a furnace includes a coupling box extending between a primary heat exchanger and a condensing heat exchanger. The coupling box defines a flow path for flue gas between a primary heat exchanger outlet and a condensing heat exchanger inlet. A tube sheet is located at the condensing heat exchanger inlet and a liner is located at a distance from the tube sheet in the coupling box. The liner and the tube sheet define an insulating liner space therebetween reducing condensation on the liner.

Abstract: A furnace includes a cabinet having a top plate and a blower located in the cabinet. A blower shelf is located in the cabinet and has a first side supportive of the blower and a second side including one or more canted slide rails. A heat exchanger is located in the cabinet between the blower and the top plate and is securable to the one or more canted slide rails. The one or more canted slide rails are configured to allow removal of the heat exchanger from the cabinet along the canted slide rails without removal of the top plate from the cabinet.

Abstract: A condensing heat exchanger (100, 100a) is disclosed that includes a pair of opposing half shells (145, 145a) connected together. The half shells (145, 145a) define an inlet (111) at one end and at least one outlet (112, 113) at an opposing end of the heat exchanger. The pair of opposing half shells (145, 145a) also defines a central axis (133). Each half shell (145, 145a) includes a plurality of elongated angled beads (117, 117a, 119) that extend inwardly towards the other half shell. The elongated angled beads (117, 117a, 119) of each half shell (145, 145a) extend traversely across the central axis (133) at an angle ? with respect to the central axis (133). The beads of one half shell (145, 145a) also extend traversely across one or more beads of the other half shell.

Abstract: A compact gas combustion furnace includes a substantially rectangular casing having an interior defined by a plurality of compartments. A draft inducer is mounted above the heat exchanger compartment to allow a multipass heat exchanger to be used while allowing the furnace to be fitted within a mobile home closet. A transition box couples the horizontally disposed inlet of the inducer and the vertically disposed outlet side of the heat exchangers. In a preferable arrangement, the furnace includes a burner assembly utilizing a plurality of burners, each having an arcuate shape in relation to a corresponding plurality of heat exchangers, and thereby occupying a minimum of space without loss of efficiency.

Abstract: A forced air furnace has its blower mounted on a blower shelf beneath the heat exchanger, by screws that enter aligned clearance holes in the blower mounting flanges and blower shelf and which engage gripper holes in a bottom lip of the vertical cell panel that serves as the proximal wall of the furnace heat exchanger cell. This provides vertical support for the blower and absorbs stresses from up-and-down motion.

Abstract: In a furnace of the type having a blower shelf with a blower attached to one surface thereof and a heat exchanger unit located proximate a second surface thereof, and the heat exchanger unit being reversibly attachable to the blower shelf, the improvement comprising: a retaining structure unitary with the back panel of the heat exchanger; and a structure which mates with the retaining structure and is unitary with the blower shelf. The retaining structure and mating structure function jointly to retain the back panel of the heat exchanger unit perpendicular to and proximate the blower shelf.

Abstract: A multi-cell secondary heat exchanger for use in a high efficiency, multi-poised furnace wherein each cell has outwardly extended exit or entrance bells that are received in grooves formed in adjacent cell panels. The grooves surround exit or entrance ports and are filled with a sealing material that provides a fluid tight seal between the cell panel and the bell.

Abstract: A furnace for supplying circulated heated air to a comfort zone, the furnace having a condensing heat exchanger and a blower for moving ambient air over the heat exchanger, wherein a transformer for stepping down line voltage (115 VAC) to control voltage (24 VAC) is secured to the inner surface of an enclosed housing within the furnace wherein the inner wall also supports at least one retaining bracket and one fastenable support bracket. A first flange extending from the transformer engages the retaining bracket to rotatably support the transformer. A second flange extending from the transformer engages the fastenable support bracket to secure and further support the transformer supported within the housing. A threaded member secures the fastenable support bracket to the second flange, thereby preventing disengagement.

Abstract: A front access door suitable for accessing and enclosing a housing within a multipoise furnace functions in conjunction with a safety shutoff switch to provide greater access and safety when assembling and servicing the furnace. The front access door is hingably supported upon the bottom wall of the housing for removal from the furnace and rotation between a closed position and an opened position. The shutoff switch is mounted outside the housing on the top housing wall. When the access door moves into a closed position, a switch activator, mounted to the access door, passes over the top housing wall and closes the switch, thereby allowing power to flow to a blower within the housing. When the access door is moved into an open position, the switch activator opens the switch, thereby terminating power to the blower.

Abstract: Structural elements of weld guns are made of composites for strength, low weight and long life. Anisotropic strength structures are fabricated by making a hollow form and applying layers of carbon fabric and unidirectional tape which are aligned with the forces developed within the structure to withstand shear, tension and compression. A tough abrasion resistant fabric such as an aramid fabric is applied as a protective covering. A resin binder unites the composite structure.