Test results from a white paper report show that a canopy-hood kiln ventilation system is more effective at removing excess heat escaping from kilns, and more energy-efficient than downdraft kiln ventilation systems.

Kilns are ventilated to remove hazardous fumes and noxious odors produced during the firing process. Excess heat escapes from the kiln through peep holes and worn seals.

According to the report, “Kiln Ventilation Facts and Figures,” published by Vent-A-Kiln Corp., Buffalo, N.Y., test results show the effectiveness of a canopy-hood kiln ventilation. Test results published in the report show that with a downdraft system, temperatures in the firing room at Cone 6 reached 108°F (42°C) 10' away from the kiln, as measured 5' above the floor, and 126°F (52°C) directly above the kiln measured at the ceiling height (8'). With a canopy-hood system, room temperature measured 72°F (22°C) 10' away from the kiln at 5' above the floor, and 76°F (24°C) directly above the kiln at the ceiling height. Tests also were conducted at Cone 10 with comparable findings. To combat uncomfortable working conditions, the white paper states, using air conditioning would increase energy costs for the school or studio.

The report also includes test results comparing total energy used firing the kiln and operating the respective ventilation system. It can be downloaded from the company's website.