Juliana's thermally powered automatic window openers are an easy & efficient way to vent out unwanted heat from your greenhouse or coldframe. As heat builds up above the desired temperature, the arm activates, opening the window. As the temperature cools, the window closes, preventing the temperature from dropping too low. Works by a thermally powered piston, so there are no batteries or motors to fail.

Please Note: The Ventomax Opener cannot be used on the Mini & Basic Series.
The Univent Opener can be used on all units.
| JUA4011 | Ventomax Automatic Opener | $ 44.95 | ![]() |
| JUA4021 | Univent Automatic Opener | $ 49.95 | ![]() |