air intake input needed

[socialistpete]

So I have a 4x5x8 grow room setup running 1000w hps with 4 plants in dirt right now. My light cycle runs from 10pm to 10am. in the summer I made ducting out of cardboard and had an intake from one window running a big ass inline fan(cfm unknown it was a work freebie) an exhaust out another window with just a reversible dual window fan. But now the winter. I'm not using the inline fan from the intake and the exhaust only when the light is on. The problem is that the air that passively enters during the day gets my room to cold, well not to clod most of the time seen as its still around 45degrees at lowest yet, but it has a few times. when the light is on just using the exhaust fan to vent keeps it between 71 and 80 right now. Will not drawing fresh air in from the outside cause any major difference? Should I just vent the grow room with air from the room its in now? Any suggestions would be great.:thumbsup:

socialistpete Reviewed by socialistpete on 10-29-2007. air intake input needed So I have a 4x5x8 grow room setup running 1000w hps with 4 plants in dirt right now. My light cycle runs from 10pm to 10am. in the summer I made ducting out of cardboard and had an intake from one window running a big ass inline fan(cfm unknown it was a work freebie) an exhaust out another window with just a reversible dual window fan. But now the winter. I'm not using the inline fan from the intake and the exhaust only when the light is on. The problem is that the air that passively enters Rating: 5

[spongebobsmokepants]

can you stop the air from seeping in during the dark period? The outside air exchange is good, but not mandatory. you can exchange the air with other parts of the structure and keep that heat inside where it belongs in winter.(lower heating bills)

[socialistpete]

can you stop the air from seeping in during the dark period? The outside air exchange is good, but not mandatory. you can exchange the air with other parts of the structure and keep that heat inside where it belongs in winter.(lower heating bills)

I was thinking of a way to stop the air from entering during the dark cycle. right now the duct is square about 6inx6in so i was thinking about building a small box to put in the window with a 3 in pvc pipe that would connect right to some other squirrel type fans I have. Right now the windows are about wide open with a closed white blind and then cardboard duct taped behind that and the duct work connected to that. So if I do it the way I'm thinking maybe if the only opening is 3in it will allow just a little air through and help with the temps in the dark cycle.