This Fire Chief FCOS1600 add-on furnace combines exceptional quality at an affordable price. MADE IN THE USA The FCOS1600 comes standard with a round firebox. This creates a strong fire chamber and also increases the surface area for greater heat transfer. Works with existing furnaces and HVAC duct work to heat up to 1800 square feet Easily connects to existing duct work Automatic Heat Dump Door - PATENT PENDING-Safely releases heat off the unit in the event of power failure Secondary Combustion Chamber-Increases fuel efficiency while re-burning smoke and wood gases before they are vented up the chimney, resulting in a cleaner burn. Pre-Wired Electrical System - Fully automatic components are pre-wired for your convenience and to reduce electrical installation time and expense. Thermostatically controlled 1800 CFM blower-Delivers a more consistent heat in the home Manual Draft Control-Easily adjusts the temperature setting in your home with the cast iron door mounted spin draft controls. Laser Cut Ash Slots-Allow fine ash to drop into Ash Pan leaving hot coals in the firebox. High Temp Insulation Deep Firebox (Holds 28'' Log) Slide By-Pass Damper-Makes cleaning flue easier and aids in quick fire start-up. Cabinet has a durable, weather-resistant baked on powder coated enamel finish Ash Drawer with Draft Damper Cast Iron Fuel Door High Grade, heavy (7 & 10) gauge steel is continuously welded for maximum structural strength. Specifications Height: 44.5'' Width: 29.5'' Depth-includes Filter Box: 60'' Log Size: 28'' Fire Chamber Volume: 6 Cu. Ft. BTUs - Maximum: 100,000 Heating Capacity: 1,800 sq. ft. Door Size: 13'' x 14'' Blower Capacity: 1800 cfm Blower Power Supply (Volts, Amps): 110, 20Warranty - Fire Box: 5 year limited Warranty - Electrical Components: 1 year Hot Air Plenum: 10'' round Cold Air Return: 12'' round Optional Accessories for the Fire Chief FC1100 Wood Furnace Heating System: AM-BD10 - 10'' Back Draft Damper (Supply Air)AM-BD12 - 12'' Back Draft Damper (Return Air)*The BTU ranges and heating capacity Specifications are provided as guidelines only and in no way guarantee the output or capacity of the unit. The actual BTU output depends on the type of fuel being burned and its condition, the draft adjustment and the chimney that the unit is hooked up to. The actual area that the unit will heat depends on factors such as the condition of the building, heat loss, type of construction, amount of insulation, type of air movement and location of the unit.