how often to vent a sealed room with no co2

does anyone grow sealed using no co2? how often do you vent?

i ask that because here the outside temps reach into the 100's and so if i vented to often the temps wont stay down.

i plan on using a split unit ac where the condenser sits outside and the heat exchanger is in the room. here is a link below

http://www.younits.com/fujitsu-12rls-halcyon-wall-ductless-heat-pump-25-seer-12000-btu-p-1320.html?utm_source=Google+Base&utm_medium=cpc&utm_campaign=comparison_shopping

You may want to post that question on the Indoor grow forum.

once plants get a sorta big, iv heard they use 1sq ft. of O2 per hour. this is just hear say tho, IMO its more like 1 sq ft. per 3-5 hours. so it really depends on the size of your room.

oops thought i was in indoor section any ways the flowering room is 12 x 24 x 8 feet.

mods can you move this post please?

thats a good size room, i would vent it once a night right befor lights go out just to be safe though.