The Automatic Vent Opener was designed to automatically control 
the temperature and humidity amounts and offer additional ventilation when needed, making gardening easier. As the atmosphere inside the greenhouse warms, the vent steadily opens to enable the right amount of air flow in to the greenhouse and closes when the temperature cools. The vent arm was made with a metallic cylinder containing wax which expands when heated to force a piston, which raises the windows, as the air gets warmer, then agreements as it cools, closing with the use of a spring and resetting the piston. All you have to to do is to install it on your own roof vent home window and it instantly starts functioning. The Automatic Vent Opener functions without the use of electricity and works with with all Palram greenhouse models only. The solar powered Vent Opener will start to open as temperatures within your greenhouse reach 68 degrees F with full-open at 80 degrees. It installs efficiently and will Automatic Greenhouse Vent provide care-free ventilation.
Ingenious temperature-sensitive device that automatically opens and closes coldframe lids, greenhouse windows and even skylights. Works during the day and maintain a continuous interior climate, something impossible to achieve by manual adjustments.
Requires no batteries or electricity.
It could be adjusted to start opening between 60-77°F. Fully open at 86-90°F. Fully closed at 55°F.
Strongly recommended for every our glazed season extenders since it dramatically increases plant growth.
The hydraulic cylinder includes a 1 year warranty. The common duration of the cylinder is 5-10 years, even though some can last up to twenty years.
Screw straight into polycarbonate panels, wooden, or metal frames. THE TYPICAL Vent Opener can open a hinged windowpane or vent weighing just as much as 32 lb. For bigger panes use the more powerful Gigavent with all steel building, to lift up to 65 lbs.
Note from the maker: Suggested to lubricate the piston rod yearly, this will help extend the duration of the hydraulic cylinder. Don’t use solid grease, as dirt particles “glues” quickly onto the piston rod and may harm the rubber. Also don’t forget to unlock the vent in the wintertime if leaving the vent openers set up. Even a weak winter sun can temperature the hydraulic cylinder sufficiently to create it start pushing the piston rod outwards.
This solar vent control will open and close vents, in your solar gem greenhouse. It features two closing springs for extra power. The solar vent opener is the only solar-powered control with a quick-release mounting bracket. Just grasp the “clutch” arm and squeeze for easy detachment. This allows vent to be completely opened for access to the interior.