How to Pick Out a Ventless Gas Fireplace
The heat output can vary from 20,000 to 40,000 British thermal units (BTUs). To figure out the maximum BTUs for a room, multiply the room's length, width, and height to get the cubic feet of the room. Then multiply by 20. For example, if a room is 1,400 cubic feet, it should not radiate more than 28,000 BTUs.