Price: $38.95
Availability: Back Order - Expected to ship in 3 to 4 weeks.

The Univent allows solar powered control of top and side mounted window vents thanks to its dual springs. Univent window openers have an adjustable opening temperature of 60° F to 75° F and an 18" maximum opening which would be reached at approximately 20° to 30°F above opening temperature. Univent openers are made from corrosion resistant materials including aluminum and stainless steel. Univents also feature a unique quick disconnect feature on the bottom of the unit which is useful when using the opener with a cold frame. This model is recommended for use with Grow More, Solar Harvest, & most other greenhouse vents. Order more than one and save!

Univent Features

  • Adjustable opening temperature of 60° F to 75° F
  • Maximum opening of 18"
  • Recommended for vents up to 15 lbs.
  • Quick disconnect feature for cold frames
  • Equipped with dual springs 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

Univent Opener Instruction Manual
Univent Opener Installation Video

Overall Customer Rating of 16 Reviews:

Works well

Works as described, easy to install

auto opener for new greenhouse

The openers came quickly and all is as advertised. Waiting for our new greenhouse to get here and get them installed.
Will definitely purchase from ACF again!

NW Arkansas

Replacement part for FREE!

Got unit, tested it; tube didn't seem to work. Called company; they sent me a replacement tube (for FREE) immediately!
They will definitely get more business from me.


I installed this on an Aluminum Framed 6' x 6' greenhouse in SW Ohio.
Installation instructions were easy to follow.
Functions as stated. Vent opens on sunny 25 degree days with out a problem.
Closes tight at night.
I will be making a new lower greenhouse mounting plate out of CRS to minimize flex (personal preference)


univent automatic vent opener

Clear instructions, easy to assemble and works like a charm. I couldn't ask for more.