Hi there summers coming up things are heating up can someone please tell what size carbon filter i should be using and what size fan for pulling air in my room is 12ft 12ft by 9ft high im using a7inch extractor venting into the celling and the same size for pulling air in and its not doing the job the heat gets up to 35-38deg with the door shut this is a big problem for me because Ive got the door open all the time and the smell goes in every room plus I'm running 2x 1000 and a600 for veg ill rather ask the uk420 community for help other than the local grow shop

just a guess mate but i would say you will need fans bigger than 6" in a room that size

but wait for someone who actually knows what to tell you for certain

in that space loads mate i have no true answer but i would say at least 2x10inch out with 2 10inch carbon fillters
and 2x8 intake

http://www.uk420.com/growroomtools2.php

thanks guys hughie green your a champion

summers coming...lucky boy...maybe for you...the rest of us are heading into a rotton winter.....enjoy

If you were in the UK you would need a 10" RVK or Ruck, high powered version fan. If you're not in UK, what is the highest common temperature in your summer, excluding one or two freak high temperature days.

Fan size and power is dependent on light heat load and the temperature of incoming air. The grow tool does NOT include light heat load allowance.

summers days are around 28-30deg freak temp around 35-38 winters a good time for me.

would it not be more wise to use cooltube reflectors to drop your temps m8?

Assuming a target grow temp of 28 deg C, in your summer weather, even when possible, you would have to have something like 4 number 10" high powered fans and CFs. That obviously is ridiculous, so you could only achieve it by having air conditioning, i.e. have the capacity to cool incoming air. I'm a vent person so you should wait for a person more knowledgeable on tolerable temperatures. 28 deg seems to be the consensus on this site for target grow temps.

Thanks for that daviie looks like i have to down size things