Ingenious temperature-sensitive device that automatically opens and closes coldframe lids, greenhouse windows and even skylights. Works throughout the day and maintain a constant interior climate, something impossible to achieve by manual adjustments. Requires no batteries or electricity. It can be adjusted to start opening between 60-77°F. Fully open at 86-90°F. Fully closed at 55°F. Strongly recommended for all our glazed season extenders because it dramatically improves plant growth. The hydraulic cylinder comes with a 1 year warranty. The average lifetime of the cylinder is 5-10 years, although some can last up to 20 years. Screw directly into polycarbonate panels, wood, or metal frames. The Standard Vent Opener can open a hinged window or vent weighing as much as 15 lb. For larger panes use the stronger Gigavent with all metal construction, to lift up to 65 lbs. Note from the manufacturer: Recommended to lubricate the piston rod yearly, this will help extend the lifetime of the hydraulic cylinder. Don't use solid grease, as dust particles "glues" easily onto the piston rod and can damage the rubber. Also do not forget to unlock the vent in the winter if leaving the vent openers installed. Even a weak winter sun can heat the hydraulic cylinder sufficiently to make it start pushing the piston rod outwards. Replacement cylinders are available.Related supplies: Shop greenhouses and accessories to compare compatible fabrics, structures, fasteners, and accessories.
