We leave our small horizontal air flow fans on 24/7, but we do turn them
down a little slower in the cooler weather. The exhaust fans are on
thermostats and only come on when needed for cooling.
--
Kenni Judd
Juno Beach Orchids
http://www.jborchids.com

"Rob Halgren" wrote in message
...
kenty ;-) wrote:

Has anyone got any comments on running a fan in a greenhouse 24/7.Does
this
have any cooling affect costing more to run the heater in winter or just
circulate the air inside the greenhouse?I am running a fan all the time
at
the moment,to provided air movement and the atmosphere becoming stagnant
,possibly causing rots/infections etc.As the temps are cooler and
humidity
higher.I only have a 10x8 greenhouse.



I certainly think it is traditional to leave the fans on 24/7. And
a pretty good idea. It wouldn't have a real cooling effect in the
winter, I suspect it is going to have a net positive effect on your heat
bills by moving warm air off the ceiling and down to the floor.

Curiously (or maybe not), just last night I was wondering about the
wisdom of leaving all my fans on all the time. I have a lot of fans (8
big ones in a 1500sq ft greenhouse). I could probably keep air moving
with just a couple fans at night, and put the rest on timers. Then I
started thinking about condensation, and how a whole lot of air movement
probably keeps the cold water drips to a minimum, and wondered about
leaving them on all the time anyway... Needless to say, I'm still
wondering...

Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) When one has insufficient credit to purchase
more orchids, obtain more credit
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