Vent Openers & Fittings

Vent openers are the ventilation made in the roof or side walls of the Green Houses, to let the fresh air come in. Vent Openers are of various types, some are solar powered, and some are automatic.

 

Automatic Vent Openers
Vent openers do not require electricity. The opener has a metal cylinder containing a mineral which expands when heated. This pushes a piston that opens the vent. As the temperature cools, the mineral shrinks and a spring closes the vent and resets the piston. The opening and closing of the vent is gradual allowing just the right amount of air flow for cooling.

 

Solar Powered Vent Openers
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 power tube 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. This allows the opener to be installed on the roof or a side wall.