I have a natural gas burner: How much flue discharge will I have in cubic feet per hour? How much combustion air is required in cubic feet per hour??
The amount of air required by the gas combustion burner on the Tornado 60 Washing machine. This machine was shipped with a 380,000 BTU/hour capable burner. The amount of air required to burn natural gas is a fixed amount. Adding in about 3% excess air for safe combustion the rule of thumb is that it takes 10 cubic feet of air for every cubic foot of gas. Unless you know the BTU/cubic foot of natural gas in your area another rule of thumb is to use 1000 BTU/cubic foot. Abbreviations: Hr = Hour CFH = Cubic Feet per Hour Cu ft = cubic feet So the things you need to know are: The burner firing rate – assume burner is adjusted to 380,000 BTU/hr Natural Gas Specific Heat – assume 1000 BTU/Cu ft Assume 10 CFH of air per CFH of gas We then have for the flue discharge: 380,000/1000 = 380 CFH of gas 380 CFH gas * 10 cu ft of air/cu ft of gas = 3800 CFH of air.
