W255G Cozy Gravity Wall Furnace 25K BTU  Cozy Gravity Wall Furnaces mount on any inside or outside wall with 16" center stud space and provide both circulated and radiated heat – a preferred combination! It provides economy and flexibility of operation and allow individual temperature control in “hard-to-heat” areas. Cozy is a perfect answer for either new construction or remodeling heating applications. Specifications: Type Gas Natural with 1/2 inch gas inletBTU Input Per Hour 25,000  Vent Pipe Opening 4"Floor to Center of Vent 22"Min. opening required: 65-3⁄4 H x 14 -1⁄4"WFinished Dimensions: 16-1/2" W ✕ 68-3/8" H ✕ 6-1/2" D *Model W255G replaces model W255F