Outdoor heating furnaces are basically wood fired boilers housed outside of a home.
The distance between the heat source and the location to be heated can be as much as a hundred yards apart. The furnace can heat either glycol or water where it’s pumped through insulated pipes to your home. The heated liquid can supply heat in several ways, such as liquid to liquid heat exchanging, direct heat, and also through a hot air radiator. In a liquid-to-liquid heat exchanging system, the heated liquid enters a large storage tank containing coils of copper tubing, then water in the tubing is heated and this flows through the hot water baseboard set up in your home and supplies all your hot water needs! Direct heat is when heated liquid enters the home and goes directly into the home’s hydronic system and indirectly heats the water in a separate system. When using a hot air radiator, heated liquid can be pumped through inside the plenum of a forced-air system. Using the air duct of an existing heating and A/C system, the radiator transfers the heat to the air which is then distributed by the fans of the furnace when the control device comes on. All outdoor furnace systems are closed loop systems meaning that the cooled liquids return to the heat source via a return tube and are reheated again. Keep in mind the three types of outdoor gas furnaces that there are and correctly choose the right one for your home and specific needs.