Having trouble keeping temps in tent below 80 degrees. I have a 2x4x60 tent with a spider farmer g4500 light. I have a 4 inch in line duct fan with carbon filter and 2 6inch fans running while lights are on. Also have duct coming in tent from ac vent. Once lights have been on for couple hours temps climb to 85 degrees in tent can’t figure out how to keep it cooler. Also I have driver for light outside of the tent. Any help greatly appreciated.
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85 degrees is ok my tents run in the mid 80s in the summer I vent my tents outside during the summer months that helps my lung room say cooler
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where are you exhausting from your tent…you should be exhausting thru the top and sucking air from the bottom…inline fans do not produce as much volume as a exhaust fan…you may want to purchase a good exhaust fan …if your 6inch fans are pointing down at your cannapy you may creating a slight air barrier…I believe in tents your fans should be on the floor pointing up to help the natural air movement thru the tent
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Like @Retiredoldguy said, your inline fan might not be moving enough air. Did it come with a cut sheet or specifications that say the CFM’s that it moves?
In a 2x4 with your light driver outside, a good 4 inch exhaust fan should have no trouble keeping temps in check as long as everything else is in good order and the air it’s pulling in is cooler.
Any chance your filter is clogged and slowing down the fan? Also, pics of your set up might help us identify something. Any bends, turns, or elbows in your exhaust ducting will also reduce CFM’s.
Do you have all available ports/socks/vents on the bottom of the tent open to allow the most airflow possible?
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@Retiredoldguy gotcha covered. Is the driver on your light removable? If so you can relocate that outside the tent to help a little 
80F isn’t so bad… I use Co2, so it’s a little different (and RDWC with a chiller), but I try to keep my tent <85F (not always successfully). Haven’t had a problem, I think.
Gotta move more air or bring in colder air. Although you can flower marijuanna successfully at 85 degrees, imo the flowers will be much better if below that 80 mark. For me the buds will be more dense and mature sweeter with slightly cooler temps. Higher temps will make more airy buds in my opinion and possibly even foxtail. Not always easy to get temp in sweet zone depending on time of yr. For example, this yr im waiting untill august to start back up, mainly bc i will get the warmer temps and higher humidity for seedling/veg stage, but switch to flower start of october to fight the heat from the switch to flower and more wattage. Personally i cannot justify adding ac because at that point im not really saving money when oz’s here are 100 bucks for a+ weed
I’m also running a 2x4 tent with the same light that you are. It really didn’t get too hot until I cranked up my light for flowering. I’ve found that controlling conditions in the lung room makes keeping things stable inside the tent a lot easier. my lung room is usually low 70’s and if the tent is getting above 80, I’ll unzip the bottom and place a gallon water jug there to hold the flap open a bit to allow more cool air in. I’ve never had it get over 82 though, do you have other equipment inside the tent? Like a dehumidifier? Dehumidifier will throw off a lot of heat inside the tent and you’d be better off if it was sitting outside the tent drying out the lung room air.
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I fight daily trying to manage 85 in my veg room… supposed to get up to 90 this weekend… sheesh
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Thanks for all the advice greatly appreciated. I am pulling air out the top of tent and have cool air from ac vent coming in at bottom of tent. I have all vents open on tent. I put both fans in bottom of tent blowing up like someone mentioned earlier and so far so good. Lights came on at 4 this afternoon so going to watch it tonight and see what happens. Fingers crossed.
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Your reply just answered my question before I could ask. Going to move fans to bottom facing up. Love this forum
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