aircool question.

I have recently bought inline fan. If I pull air in from outside. Will really could air crack hot bulb. Like winter air. Thanks.

You will be ok

Be sure to scrub the air or youllrisk pulling in bugs, spores, plant diseases and just bad shit in general
You should be good as far as cold air breaking bulbs tho

no just make sure it warms up as the air is going through it...freezing air instantly on a fully heated bulb could be trouble

like putting a hot pyrex dish out of the oven into the sink and turning on the water.... instant glass dish shatter everywhere.