Replace your old furnace with a lighter weight, more efficient Atwood propane furnace to keep your RV comfortably warm when temperatures drop. Increased cubic feet per minute of air flow exchanges air 10% faster, heating coach quicker. Replaces previous 8900 series but does not use the same cut-out size; requires bottom discharge kit and/or trim ring (both sold separately). More even air flow through the heat exchanger reduces hot and cold spots. Dimensions: 9"H x 16 ½"W x 20"D. The most duct configurations in the industry provide additional heating runs for maximum air distribution and floor plan flexibility. Tubular design residential style heat exchanger maximizes air distribution. Reduced air turbulence for noticeably quieter operation. Vertical or horizontal mounting options allow for increased flexibility in design. Access door and thermostat sold separately Noticeably quieter operation Heats coach quicker Weight savings reduces fuel consumption & adds carrying capacity | Dometic Atwood RV Large Furnace, 9"H x 16 ½"W x 20"D, 40,000 BTU 12VDC