Effect of a gas furnace chimney on the air leakage characteristic of a two-storey detached house.

Reports the results of an experimental assessment of the effect of a chimney on the air leakage characteristic of an unoccupied two-storey detached house heated by either gas or electric furnace. Measurements were taken of air tightness values and air infiltration rates with the chimney capped anduncapped. Infiltration rates were also measured during operation of the electric furnace.< Finds that the overall air infiltration rate is greater with the gas furnace than with the electric furnace under the same weather conditions, and that the difference is smaller than the air flow rate through the chimney. When the gas furnace is in operation, stack action is the dominant driving potential for air infiltration with wind speeds up to 7m/s and with inside to outside temperature differences greater than 20K.