The Automatic Vent Opener was made to automatically control the Automatic Greenhouse Vent temperature and humidity amounts and offer additional ventilation when needed, making gardening easier. As the air within the greenhouse warms, the vent steadily opens to allow the right amount of air flow in to the greenhouse and closes when the temperature cools. The vent arm was made with a steel cylinder that contains wax which expands when heated to force a piston, which raises the screen, as the surroundings gets warmer, then contracts as it cools, closing with the use of a springtime and resetting the piston. All you have to to do is to install it on your own roof vent windowpane and it immediately starts working. The Automatic Vent Opener works without the use of electricity and is compatible with all Palram greenhouse models only. The solar powered Vent Opener will begin to open as 
temps within your greenhouse reach 68 degrees F with full-open at 80 degrees. It installs efficiently and can provide care-free ventilation.
Ingenious temperature-sensitive device that automatically opens and closes coldframe lids, greenhouse windows and actually skylights. Works during the day and maintain a continuous interior climate, something not possible to accomplish by manual adjustments.
Requires no batteries or electricity.
It can be adjusted to begin opening between 60-77°F. Fully open at 86-90°F. Fully closed at 55°F.
Strongly recommended for most our glazed season extenders because it dramatically enhances plant growth.
The hydraulic cylinder includes a 1 year warranty. The common duration of the cylinder is definitely 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 up a hinged screen or vent weighing as much as 32 lb. For bigger panes use the more powerful Gigavent with all metal building, to lift up to 65 lbs.
Note from the manufacturer: Recommended to lubricate the piston rod yearly, this can help extend the lifetime of the hydraulic cylinder. Avoid solid grease, as dust particles “glues” quickly onto the piston rod and will harm the rubber. Also don’t forget to unlock the vent in the wintertime if departing the vent openers set up. Even a weak winter sun can heat the hydraulic cylinder sufficiently to make 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 strength. The solar vent opener may be 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 fully opened for usage of the interior.