Combustion requirements in an unconfined space

Larry Richardson

We’ve talked about the critical need for providing enough air for proper combustion in this publication before, but as houses get “tighter” and infiltrating air gets scarcer it’s worth reviewing.

In the November 2009 issue of OilHeating Magazine, they printed a handy table showing approximate square footage of rooms required per burner firing rates necessary to provide for proper combustion when direct outside air is not available. One example used is for a burner with a 1.00 gph firing rate, a minimum room size of 7000 cubic feet is required. Based on a standard ceiling height of 8 feet, the room would need to be close to 30’ x 30’. Always keep in mind that if additional appliances are dependent on the room air, allowances must be made and the room size would need to be larger. In addition, when calculating room size, be sure to deduct the space taken up by the appliances and any other objects present such as a fuel oil tank.

For help in determining whether adequate combustion air is available the table referenced above can be very helpful. If you would like to discuss your project, please call our Liberty office and ask for Larry or Rick.