This is a pre-existing zero clearance gas fireplace with a 10" Class A double-wall pipe. While helping a friend replace his chase cover I thought the flue looked a little small. The fireplace opening is 44" wide and 36" height, 30' tall chimney.
When determining the exhaust size of a 150,000 BTU gas fireplace (if that makes a difference), do you use the same type of calculation as if you were using a wood fireplace? Width x Height and divide by 10 or 12 depending on the chimney height? Can a external exhaust fan be used to make up the difference if the pipe is to small?
When determining the exhaust size of a 150,000 BTU gas fireplace (if that makes a difference), do you use the same type of calculation as if you were using a wood fireplace? Width x Height and divide by 10 or 12 depending on the chimney height? Can a external exhaust fan be used to make up the difference if the pipe is to small?