Bayliss Autovent Opener

This non-electric roof vent opener is simple to install and is completely automated. A threaded adjuster bolt can set the Bayliss to start opening the vent at approximately 55 degrees fahrenheit. This vent opener uses a very simple principal - Special waxes have an expansion rate of about 18% when heated by the sun. As the air in the greenhouse heats up it also heats the powertube in the vent opener. As the wax expands it pushes out a stainless steel piston that slowly opens the vent up to 13 inches. The hotter the temperature the wider the opening. When the temperature cools the weight of the vent and a 6 1/2 pound stainless steel spring closes the vent and holds it closed.

Additional Information

Manual

Bayliss Autovent Opener (PDF)