Move and refresh the stagnant air in your greenhouse or building to make a healthier and more productive growing environment. These greenhouse exhaust fans are great for reducing plant and worker heat stress. Our exhaust followers provide exceptional ventilation for high tunnels and cold frames. Create a cooler more comfortable growing environment, which can directly contribute to productivity, quality and profitability for your greenhouse business. Exhaust supporters also functions great in workshops and buildings.
Move and refresh the stagnant air flow in your greenhouse to create a healthier and more productive environment. These exhaust & circulating fans are great for plant development. Create a cooler convenient growing environment, which can 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 had some type of vents or louvers which were opened to enable the excess heat to escape and cooler outside surroundings to enter.
When polyethylene originated with large sheets within the whole roof, placing vents on the roof proved difficult. Engineers after that came up with the concept of using enthusiasts 
that pull outside air flow through louvers in a single endwall and exhaust it out the Greenhouse Vent Fan contrary end. With thermostatic control, this was, and still is the accepted way for cooling many structures where positive air flow movement is needed.
Growers with hoophouses have discovered that roll-up sides work very well for warm season ventilation. Both manual and motorized systems can be found. A location with good summer season breezes and plenty of space between houses is needed. It helps to have greenhouses designed 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 operate on the principle that heat is removed by a pressure difference created by wind and temperature gradients. Wind performs the major role. In a well designed greenhouse, a wind swiftness of 2-3 miles/hour provides 80% or even more of the ventilation. Wind passing over the roof creates vacuum pressure and sucks the heated air flow out the vent. If sidewall vents are open, cool replacement air enters and drops to the ground level. If the sidewall vents are closed, cool air enters the bottom of the roof vent and the heated are escapes out the top of the vent.
