Price: $125.00
Availability: Out of stock until April - May.

This is the strongest vent opener we offer. It has a hydraulic cylinder which provides superior protection in windy areas. Opening temperature can be adjusted from 56° F to 70° F and maximum opening of 18" is reached at approximately 20° F above opening temperature. Gigavent cylinder can be installed in many different positions for maximum mounting flexibility. This model is too large for use with all of our greenhouses except some of the Cross Country models.


  • Adjustable temperature range of 63° F to 77° F
  • Maximum opening of 18"
  • Recommended for vents up to 100 lbs. total weight
  • Equipped with built-in damper for windy locations
  • Made in Denmark

How does a Greenhouse Autovent work?
A strong metal tube contains a mineral wax which expands with heat. This pushes a piston which opens the auto vent via a balanced linkage. As the temperature drops, the wax shrinks and a strong spring closes the vent and resets the piston.

Product Manuals, Tips, Specs, & Guides

Gigavent Vent Opener Installation Manual

Overall Customer Rating of 2 Reviews:
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Weston, Colorado

Great Product & Thankful for Replacements

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The Gigavent is a great product that allows me to control the heat in my greenhouse. The simple heat/solar technology makes it all the better. The only downside is that the heat-activated pistons eventually give out and the occasional wind gusts bend the mechanisms. For me, a small price to pay for the benefit I get. ACF has this product(s) at a good price and ships fast. What more could you want?

Best Vent Opener on the Market

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Just installed 2 Gigavent openers in my greenhouse. Both vents are 2 ft x 8 ft. The Gigavent has worked well. Installation was a bit of a chalenge but with a piece of 2.5 in angle aluminum I was able to make brackets that made installation easier. It appears that the Gigavent requires 2 surfaces to mount on which are 90 degrees from the opening direction of the vent as shown in the instructions. It would be nice to have installation on at least one surface which is along the surface of the vent. The aluminum angle piece solves this problem. Overall I am pleased with the Gigavent. It replaced a Bayliss unit which is a little more than half the price but basically a piece of junk. The Bayliss worked for a couple of years then gave out and even a cylinder replacement only allowed 1 more year of spotty performance. The action of the Gigavent is much smoother and opening and closing is silent, unlike the Bayliss.