Move and refresh the stagnant air in your greenhouse or building to make a healthier and more productive growing environment. These greenhouse exhaust followers are excellent for reducing plant and worker heat stress. Our exhaust supporters provide exceptional ventilation for high tunnels and chilly frames. Create a cooler convenient growing environment, which can directly contribute to productivity, quality and profitability for your greenhouse business. Exhaust enthusiasts also functions great in workshops and buildings.
Move and refresh the stagnant Greenhouse Vent Fan atmosphere in your greenhouse to make a healthier and more productive environment. These exhaust & circulating fans are excellent for plant growth. Create a cooler more comfortable growing environment, that may directly contribute to productivity, quality and profitability for your greenhouse business.
The idea of cooling a greenhouse with thermal buoyancy and wind goes back to the start of controlled environment. All greenhouses constructed just before the 1950’s acquired some kind of vents or louvers which were opened to allow the excess heat to escape and cooler outside atmosphere to enter.
When polyethylene originated with large sheets within the whole roof, putting vents on the top proved difficult. Engineers then came up with the idea of using fans that attract outside surroundings through louvers in a single endwall and exhaust it out the opposite end. With thermostatic control, this was, and still is the accepted method for cooling many structures where positive air movement is needed.
Growers with hoophouses have discovered that roll-up sides work very well for warm period ventilation. Both manual and motorized systems are available. A location with good summertime breezes and lots of space between homes is needed. It helps to have greenhouses made with a vertical sidewall up to the elevation of the attachment rail to reduce the amount of rain that may drip in.
Greenhouses with roof and sidewall vents are powered by the principle that heat is removed by a pressure difference created by wind and temperature gradients. Wind plays the major part. In a smartly designed greenhouse, a wind speed of 2-3 miles/hour provides 80% or more of the ventilation. Wind 
moving over the roof creates a vacuum and sucks the heated atmosphere out the vent. If sidewall vents are open up, cool replacement air flow enters and drops to the ground level. If the sidewall vents are closed, cool air enters underneath of the roof vent and the heated are escapes out the top of the vent.