Abstract: A telescoping roof jack assembly for a furnace includes a pair of outer telescoping tubes and a pair of inner telescoping tubes. At least one of the pairs of tubes is provided with cooperating detents which prevent the telescoping tubes from separating. A plurality of connectors are attached to one of the inner tubes and extend slidably through openings in one of the outer tubes. The connectors cause the inner and outer tubes to telescope together while permitting relative transverse movement between the inner and outer tubes.

Abstract: A heat exchanger assembly for an undercounter furnace includes first and second complementary, flanged sidewalls shaped to provide a fire chamber. Integral lower combustion air intake and upper exhaust flue are formed from the same sheet metal as the sidewalls. The width of the fire chamber is less than its height and length. A circulating fan is located behind the fire chamber and between the intake and flue ducts, taking room air from the rear of the casing and forcing it forwardly to sweep over both sidewalls and into the room to be heated. The heat exchanger is mounted to a removable chassis.

Abstract: An air terminal for a horizontal vent of a sealed combustion furnace includes a faceplate for mounting to an exterior vertical wall. A horizontal flue pipe extension, receiving the combustion products, is surrounded by an oval sleeve. Fresh air is communicated to the furnace through the space between the flue pipe and the sleeve. The outlet of the flue pipe is at least about 3/4 in. outside the faceplate. An enlarged fresh air intake opening exists about the flue pipe, and a pocket-shaped rain shield is located beneath the flue pipe extending upwardly and inwardly. A horizontal wind deflector vane is located beneath the flue pipe and extends across the width of the fresh air intake opening for directing incident wind downwardly along the wall. The terminal improves operation of the furnace under all wind conditions, whether the furnace is operating on pilot or main burner modes.