Abstract: An improved air actuated damper device (10, 30) is described. The damper comprises a cylindrical conduit (11, 31) that can be joined to a flue pipe (17) at a proximal end (11b, 31b) of the damper device; a damper support beam (13, 33) across the conduit offset above a longitudinal axis (a-a, c-c) of the conduit; and a damper blade (15, 35) that pivots on a pivot axis (b-b, e-e). The damper blade is comprised of an upper section (15a, 35a) and a lower section (15b, 35b) so that the damper blade pivots on the pivot axis and opens when gas flows through the conduit and closes to seal against sealing lips (11e, 31e) and 11f, 31f) extending from and into the conduit when there is no gas flow. The device provides reliable dampering for the flue gas exhaust of a furnace.

Abstract: An assembly using horizontally oriented heat exchange pipes (10, 10a) and a blower unit (11) for providing heated air adjacent to a furnace (100) and hot water heater (102) is described. The blower unit includes heat exchanger pipes with a downwardly inclined section (10d) and an upwardly inclined section (10e) from horizontal to and from a low point (10c) with a drain (12) for condensed liquids from the flue products exhaust pipe (10a) at the low point. The drain removes condensed liquids which are highly corrosive from the exhaust products pipe without allowing flue gases to pass through the drain.

Abstract: An improved unit (10) which supplies combustion air (A) to a furnace (100) or hot water heater (200) is described. The unit includes a switch (59) which continues the operation of motor (14) and fans (12 and 15) in unit (10) until the hot flue gases (H) are vented and to cool exhaust gas pipe (22) after the furnace and/or hot water heater cease to operate to produce heat.

Abstract: A combination powered flue products exhaust and preheated combustion air supply assembly is provided for use in association with a heating furnace so that flue exhaust products are given a positive exhaust to the outside while a balanced pre-heated combustion air supply is simultaneously and positively pulled inside. A compartmented main housing is provided having flue products exhaust and combustion air compartments. A flue products exhaust fan is provided in the flue products exhaust compartment and a simultaneously activated and driven combustion air intake fan is provided in the combustion air compartment. An outside air intake pipe is connected to the main housing so as to deliver combustion air to the combustion air compartment for delivery to the furnace area upon selective activation of the combustion air intake fan.