Abstract: A wall furnace is disclosed in which a secondary heat exchanger is provided to maximize the heat transfer efficiency of the furnace. The secondary heat exchanger faces the room to be heated but is aligned directly behind the primary heat exchanger. The length of the secondary heat exchanger is shortened as compared to the combined length of the combustion chamber and primary heat exchanger so as to reduce inefficiencies due to reheating of the combustion gases and to promote air flow and heat transfer around the secondary heat exchanger. Thus, this configuration provides for two essentially separate circulation circuits for heat transfer and maximum furnace efficiency. Separate heated air deflectors are also provided for each of these circuits. A side venting draft hood is also disclosed.

Abstract: A high efficiency gas furnace utilizes a unique premix design in combination with a pressurized/high velocity combustion process. The combustion process occurs in a combustion chamber and the high temperature high velocity products of combustion follow a circuitous route from the combustion chamber through finned tubular conduits to an exhaust. Heat from the high temperature high velocity products is transferred to the finned tubular conduits. An air blower assembly forces air across the finned tubular conduits and the combustion chamber to remove the heat from the finned tubular conduits and transfer this heat to a building or an enclosed portion thereof.

Abstract: A combination furnace including a solid fuel burning section and an electrically powered heating section. The two sections are disposed within an upright, insulated casing. A heat exchanger is provided above a fire box which constitutes the fuel-burning section. Dampers control the flow of combustion air to the fire box and the heat exchanger.

Abstract: An electrical heating unit comprising mainly an elongate open-ended conduit-pipe element for mounting in a stove, fireplace or like device for burning solid fuel and having a circulation or warm-air system which is separate from the combustion system of the stove, fireplace or like device. The conduit-pipe element is open at the ends thereof and encloses current supply cables for electrical heating elements arranged on the conduit-pipe element. The conduit-pipe element is also provided with a plurality of thermostats and is intended to be mounted in the flow path of the circulation air externally of the hearth space of the stove. Air forced into the conduit-pipe element at the bottom thereof and departing from the conduit-pipe element at the top thereof assists in cooling the current supply cables, even when a fire is lit in the hearth space of the stove or like device.