Can an Outdoor Wood Stove Be Used With a Forced-Air Heating System?

Outdoor Wood-Burning Furnace Systems

• Outdoor wood-burning stoves (also known as furnaces) provide an alternative method for home heating that supplements a home’s existing heating system. These outdoor systems consist of a wood-burning compartment surrounded by a water chamber, or water jacket. The heat generated by the wood burner keeps the water within a 160-to-180-degree-Fahrenheit temperature range. The fire is maintained by a blower fan mechanism that feeds air into the burner compartment. Once water temperatures reach 180 degrees, the blower fan shuts off and then turns back on once the water temperature drops to 160 degrees.

Water-Based Heating

• As a water-based heating system, outdoor wood stoves use underground pipes to carry heated water to the home. As long as the burner unit contains useable wood, an outdoor system will burn wood continuously; so hot water supplies remain available for ongoing home heating use. Insulated pipe lines help keep water temperatures hot as water moves underground.

  The more conventional water-based heating systems use baseboard registers or radiators to deliver heat into a home’s living space. And while outdoor wood stoves can work with conventional water-based systems, they can also deliver heat to forced-air heating systems.

Heat Exchange

• Even though water acts as the heat-carrying medium for outdoor wood stoves, these units can supplement forced-air heating systems as well as baseboard heating systems. Outdoor wood stoves use a heat exchanger unit that works alongside a home’s forced-air system. The heat exchanger consists of a tank-like compartment where hot water pipes in from the outdoor stove. This tank sits inside the plenum box that generates the forced, or blown, air within a forced-air system. As heated water circulates through the tank, the blower device blows across the tank and directs heated air through the ducts and vents of a home.

Temperature Control

• An outdoor wood stove system uses a continuous line of piping that runs to the heat exchange tank and back to the stove so that water flows back and forth between the tank and the stove unit. Since an outdoor wood stove runs continuously (provided there’s wood to burn), a separate temperature control regulates the flow of heat that comes through the ducts of a forced-air system. When the unit’s thermostat is turned on or up, the system’s blower fan blows air across the heat exchange tank, so warm air moves through the ducts. The thermostat that goes with the forced-air heating system remains set at a low level, so both systems aren’t running at the same time.