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.
Replacement cylinders are available.
Screw directly into polycarbonate panels, wood, or metal frames. The Standard Vent Opener can open a hinged window or vent weighing as much as 32 lb.
For larger panes use the stronger Gigavent with all metal construction, to lift up to 65 lbs.
We have 2 in our 8X16 and I agree with earlyer comments. Just one caution We live in an area that is windy at times. I would install a small link chain that would limit the max opening of vent to just where it stops opening itself. Our's would pull out of the cylinder as the wind grabbed the vent. It would then flap in the breeze which could damage the vent.Review by Foggy (on 2/11/14)
Easy to install (after analyzing the instructions carefully), functions smoothly and efficiently. Has already proven to be invaluable in growing early season plants.Review by Bullree (on 4/24/13)
Bought one of these 8 years ago and it's still growing strong. Absolutely essential cold frame accessory for high altitude gardens where sun is intense but nights are cold.Review by Desertographer (on 11/3/12)
I've had two of these on a cold frame and it's the difference between success & failure. Prior to installing them, we'd either forget to open the cold frame, and our things would cook. Or we'd likewise forget to close the cold frame, and things would freeze. This little gem of automation picks up where we leave off.<br /><br /> pax<br />*----->Review by Karl (on 10/19/11)