The Automatic Vent Automatic Greenhouse Vent Opener was designed to automatically control the temperature and humidity amounts and provide additional ventilation when needed, making gardening easier. As the surroundings inside the greenhouse warms, the vent gradually opens to allow the correct amount of air flow into the greenhouse and closes when the temperature cools. The vent arm was designed with a steel cylinder that contains wax which expands when heated to press a piston, which raises the screen, as the surroundings gets warmer, then agreements as it cools, closing with the use of a springtime and resetting the piston. 
All you have to to do is certainly to install it on your roof vent window and it instantly starts functioning. The Automatic Vent Opener works without the utilization of electricity and is compatible with all Palram greenhouse models only. The solar driven Vent Opener will begin to open as temps within your greenhouse reach 68 degrees F with full-open at 80 degrees. It installs quickly and easily and can provide care-free ventilation.
Ingenious temperature-sensitive device that automatically opens and closes coldframe lids, greenhouse windows and even skylights. Works throughout the day and maintain a continuous interior climate, something difficult to achieve by manual adjustments.
Requires no batteries or electricity.
It can be adjusted to begin opening between 60-77°F. Fully open up at 86-90°F. Fully closed at 55°F.
Strongly recommended for every our glazed season extenders since it dramatically boosts plant growth.
The hydraulic cylinder comes with a 1 year warranty. The common duration of the cylinder is certainly 5-10 years, although some can last up to 20 years.
Screw straight into polycarbonate panels, wooden, or metal frames. THE TYPICAL Vent Opener can open up a hinged home window or vent weighing as much as 32 lb. For larger panes use the more powerful Gigavent with all steel building, to lift up to 65 lbs.
Note from the manufacturer: Suggested to lubricate the piston rod annual, 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 damage the rubber. Also do not forget to unlock the vent in the winter if leaving the vent openers installed. A good weak winter sun can temperature the hydraulic cylinder sufficiently to create it start pressing 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 may be the only solar-driven control with a quick-release mounting bracket. Simply grasp the “clutch” arm and squeeze for easy detachment. This enables vent to be completely opened for access to the interior.