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November 18, 2019

Move and refresh the stagnant atmosphere in your Greenhouse Vent Fan greenhouse or building to make a healthier and more productive developing environment. These greenhouse exhaust supporters are great for reducing plant and worker heat tension. Our exhaust supporters provide exceptional ventilation for high tunnels and frosty frames. Create a cooler more comfortable growing environment, which can directly contribute to efficiency, quality and profitability for your greenhouse business. Exhaust supporters also functions great in workshops and structures.
Move and refresh the stagnant air 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, 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 kind 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 covering the whole roof, placing vents on the roof proved difficult. Engineers then came up with the concept of using fans that attract outside atmosphere through louvers in a single endwall and exhaust it out the opposite end. With thermostatic control, this is, and still may be the accepted method for cooling many structures where positive atmosphere movement is needed.

Growers with hoophouses possess found that roll-up sides work very well for warm season ventilation. Both manual and motorized systems can be found. A spot with good summer season breezes and lots of space between houses is needed. It can help to have greenhouses made with a vertical sidewall up to the height of the attachment rail to lessen the amount of rain that can 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 function. In a well designed greenhouse, a wind acceleration of 2-3 miles/hour provides 80% or more of the ventilation. Wind moving over the roof creates vacuum pressure and sucks the heated air out the vent. If sidewall vents are open up, cool replacement atmosphere enters and drops to the ground level. If the sidewall vents are closed, great air enters the bottom of the roof vent and the heated are escapes out the top of the vent.