Move and refresh the stagnant air in your greenhouse or building to make a healthier and more productive developing environment. These greenhouse exhaust fans are excellent for reducing plant and employee heat stress. Our exhaust followers provide exceptional ventilation for high tunnels and frosty frames. Create a cooler convenient growing environment, which can directly contribute to efficiency, quality and profitability for your greenhouse business. Exhaust followers also works great in workshops and structures.
Move and refresh the stagnant atmosphere in your greenhouse to make a healthier and more productive environment. These exhaust & circulating fans are excellent for plant development. Create a cooler more comfortable growing environment, that may directly contribute to efficiency, quality and profitability for your greenhouse business.
The idea of cooling a greenhouse with thermal buoyancy and wind goes back to the beginning of managed environment. All greenhouses constructed prior to the 1950’s experienced some form of vents or louvers that were opened to enable the excess heat to escape and cooler outside air flow to enter.
When polyethylene originated with large sheets covering the whole roof, placing vents on the roof proved difficult. Engineers then came up with the concept of using fans that attract outside air through louvers in a single endwall and exhaust it out the contrary end. With thermostatic control, this was, and still is the Greenhouse Exhaust Fan accepted way for cooling many structures where positive air flow movement is needed.
Growers with hoophouses possess discovered that roll-up sides work well for warm time of year ventilation. Both manual and motorized systems are available. A location with good summer breezes and plenty of space between houses is needed. It can help to have greenhouses designed with a vertical sidewall up to the height of the attachment rail to reduce the quantity of rain that can drip in.
Greenhouses with roof and sidewall vents operate on the principle that warmth is removed by a pressure difference created by wind and temperature gradients. Wind 
plays the major part. In a smartly designed greenhouse, a wind swiftness of 2-3 miles/hour provides 80% or more of the ventilation. Wind passing over the roof creates vacuum pressure and sucks the heated air out the vent. If sidewall vents are open, cool replacement air flow enters and drops to the floor level. If the sidewall vents are closed, cool air enters the bottom of the roof vent and the heated are escapes out the very best of the vent.