help? outside growbox +rep

[zorkan]

I have a small growroom outside like a shed 4x4x4 with a 400w hps light.
If I pull outside air (whatever temp for that day is) and exaust air back outside
will that be enuf to keep my growshed at a good enuf temp for plants to grow?
It will not work during winter time unless i install a heater but for sumer time will it work?

looking for advice, thanks

 

[Boneman]

Depends on what the outside temp you are pulling in is and how much air exchange you have.

 

[KaleoXxX]

wouldnt an outdoor grow box be a greenhouse? but your running an hps in there? thats different

the hps light should generate some heat, in the winter you may need a space heater

dont forget to put a carbon filter on your exhaust

 

[poke smot420]

yes it should work just fine. make sure its sealed well though

 

[svchop889]

What cfm is your exhaust and intake fans? what is the temp outside?

 

[atomicronick]

wouldnt the heat from your ballast warm up the shed....unless you dont want it to.

 

[svchop889]

because the 4 cubic feet of area your working with should be fairly easy to exchange air with outside considering if you had a exhaust and intake fan that moved 4 cubic feet of air per minute you would have entirely fresh air every minute. only question after that would be how quick does that 400w hps heat 4cubic feet of air?

 

[svchop889]

my advice would be to get a thermometer and if its to hot in there add ventilation fans if its too cool turn them off for awhile

 

[zorkan]

Depends on what the outside temp you are pulling in is and how much air exchange you have.

lets say its a hot summer day.. if i get enuf air flow it would be like the plant was outside as far as temp goes right?

 

[zorkan]

only question after that would be how quick does that 400w hps heat 4cubic feet of air?

thats a good question

 

[svchop889]

i think you should be fine as far as heat from the ballast and hps i would only worry about days that are 90 degrees or more just keep an eye on your soil moisture and keep the air circulating

 

[zorkan]

even if temp is 90+ with good circulation you think i will have a problem?
my goal is to atleast keep the temp in growbox the same as outside... is that possible?

 

[svchop889]

well you'll want to keep the room within a range of 75-85 degrees it shouldn't be too difficult to achieve in that amount of space. As long as it dosent get over 90 degrees its September now so it should be cooling off a bit now, your next worry will be keeping the temp up if they dont mature by november also depends on your location

 

[poke smot420]

if you had a vented hood with a exhaust fan leading right out of the shed then there would hardly be a heat problem. if you have a "wing" hood then your gonna have some problems

 

[poke smot420]

you could also put some ice in the room infront of your intake fan on real hot days. or run your shed during the night when its probably cooler out

 

[c5rftw]

In a hot summer day and a 400w light, things get very hot. above 90 is very stressful for the plant and usually stops growing. you need a thermometer so we can get some temp reading and go from there

 

[zorkan]

thanks all

 

[T.H.Cammo]

because the 4 cubic feet of area your working with should be fairly easy to exchange air with outside considering if you had a exhaust and intake fan that moved 4 cubic feet of air per minute you would have entirely fresh air every minute. only question after that would be how quick does that 400w hps heat 4cubic feet of air?

The OP is dealing with 64 cubic feet, not 4! 4x4x4 = 64.

 

[svchop889]

The OP is dealing with 64 cubic feet, not 4! 4x4x4 = 64.

yeah your right i was baked sorry... not sorry bout being baked sorry bout the miscalcuation he should still be ok though