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#207013 - 09/14/12 12:49 AM greenhouse exhaust fan speed controll
jackolsen Offline

Registered: 02/11/08
Posts: 21
Loc: british columbia canada
my wife just had green house built 16x20 ft i would like to control the tempeture in the greenhouse with the help of
a exhaust fan about 4000cfm would a vfd work and how do i controll the speed with a stat ?the motor would be about 0.5hp any one know what is the best way to do this

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#207021 - 09/14/12 05:30 PM Re: greenhouse exhaust fan speed controll [Re: jackolsen]
gfretwell Offline


Registered: 07/20/04
Posts: 9026
Loc: Estero,Fl,usa
Probably the easiest way is just a regular stat with a relay.
Greg Fretwell

#207027 - 09/15/12 02:01 PM Re: greenhouse exhaust fan speed controll [Re: jackolsen]
Alan Belson Offline

Registered: 03/23/05
Posts: 1801
Loc: Mayenne N. France
Get an automated light [window] opener, it works for free. A fan will remove plant food, [ good old carbon dioxide ] and force entry of a plethora of disease spores and spider-mites, apart from the cost of running a fan. A timed/sensed watering distibutor/mats will be better way to improve your glasshouse. I use bagged compost, not soil, and use it to pot flowers up the next year, third year as a soil improver. My little 8x6 produced 13 cantaloupe melons this year, plus 2 cucumbers a week and more tomatoes than we could eat. Best of luck next year and good eating!

Edited by Alan Belson (09/15/12 02:04 PM)
Wood work but can't!


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