Air Temperature waaay too high in 600W tent. CFM issue?

aleksandr2010

aleksandr2010

Active Member
Hi all, a quick overview of my system's factors that might impact temp:
5X5X6.5 foot mylar tent sitting in room where temp is 20 C
1 600W HID
DWC system
1 oscillating fan on floor (8" honeywell)
1 Computer-style 6" exhaust fan at the top near the ceiling (maybe 70 cfm?)
Reflector is not a "hood with glass" style, just an A-wing

I'm testing the system for how it runs and right now the thing that bothers me most is the temperature when the lights are on: going all the way up to 35-36 C(96 F). Well above the maximum of 32 C that i'm looking for. Water temp is 76 F. I'm wondering if this can be caused entirely by my lack of an exhaust fan with better CFM? How much might a 180 cfm fan change the temp?
 
BeanZyBoo

BeanZyBoo

Well-Known Member
i have mine in a closet about the same size as ur tent same room temp outside and same light, my room stays at a constant 26c with this fan, and thats with it on the lowest setting which is really silent, cant hear it at all, only a few times has it gone onto the second speed which is still pretty quiet and that is only when the heating is on
 
aleksandr2010

aleksandr2010

Active Member
BeanZyBoo said:
i have mine in a closet about the same size as ur tent same room temp outside and same light, my room stays at a constant 26c with this fan, and thats with it on the lowest setting which is really silent, cant hear it at all, only a few times has it gone onto the second speed which is still pretty quiet and that is only when the heating is on
Click to expand...
That is a VERY nice fan for a very decent price if it is as quiet as you say. I'd love to move to a 6" inline fan but I'm worried about noise. I had a cheap 4" inline fan on the system before the PC fan; but it was awful for sound so i took it off: http://aeroponicsnmore.com/climate-control-ventilation-c-23_5/atmosphere-jetfan-in-line-duct-blower-fans-p-128 This is the exact model...wouldnt reccomend it. 161 cfm and BIG noise.
 
robert 14617

robert 14617

Well-Known Member
sounds like you need a vented hood ..don't forget soil or water dependig on your medium will affect the temp ......with soil watering pushes my temps up 5*
 
D

Divitus

Active Member
I run a 170 CFM inline fan in a 5x5x7 foot tent with a single 600 watt HPS in a MagnumXXXL 6" air-cooled reflector and my temps run in no higher than 76F with the light on and no lower than 66F with the light off. I will be going to a 1k watt HPS very soon, but I will be upgrading to a 400+ CFM inline before I install the new ballast. I think you adding a higher CFM fan, will really help your temps. Oh, and if you are worried about sound, get a little higher CFM fan and turn in down to 75% or so with a speed controller and add a duct muffler. All your sound worries gone. Good luck man!
 
aleksandr2010

aleksandr2010

Active Member
I think I'll get that 6" RUCK fan with the thermostat speed changer. I'm reading around that any fan that can be turned off of its maximum speed via thermostat or any other way tends to be very quiet. Unless someone has poor noise expiriences with these fans or have other 4"-6" fans that they've found very quiet and powerful.
 
BeanZyBoo

BeanZyBoo

Well-Known Member
the fan i listed is great, just use passive intakes, set the temp and thats it, mine is in a closet behind a wooden door and like i said i forget its on, only know when it switches up to second speed but i still sleep through it and is still pretty quiet, its the best investment i made :)
 
aleksandr2010

aleksandr2010

Active Member
thanks Bean, I'll probably get that RUCK for sure, there's several other threads from the past that mention RUCK fans being really quiet. As for an inlet for cooler air, the grow tent has inlets at the bottom of the tent, where cooler air comes in and gets spread around by the oscillating fan. But I'm kind of limited where I am in what I can do for a true cold-air inlet. My situation is not such that I can do all kinds of construction and I kind of have to keep my system restricted to the borders of the room it is in, so the coolest air I can pull in is that 20 C room temp air.
 
BeanZyBoo

BeanZyBoo

Well-Known Member
aleksandr2010 said:
thanks Bean, I'll probably get that RUCK for sure, there's several other threads from the past that mention RUCK fans being really quiet. As for an inlet for cooler air, the grow tent has inlets at the bottom of the tent, where cooler air comes in and gets spread around by the oscillating fan. But I'm kind of limited where I am in what I can do for a true cold-air inlet. My situation is not such that I can do all kinds of construction and I kind of have to keep my system restricted to the borders of the room it is in, so the coolest air I can pull in is that 20 C room temp air.
Click to expand...
I pull the same temp air into my room as well, aslong as the exhausted air goes to a different area/room then u will be fine, cant u vent into an attic or a window ect?
 
FootClan

FootClan

Well-Known Member
aleksandr2010 said:
Can't vent into an attic from where it is, in the summer i can vent out of a window but currently the temperature where i am is -25 or -30 C depending on the time of day :)
Click to expand...
if you dont exhaust your old hot air outside or into an attic then you will never fix the core problem....you can upgrade to the biggest fan on the market wont matter if your just recycleing the same old hot air...If your not exhausting outside your grow is fundamentally fluad from the very beggining.
 
Mr. Beans

Mr. Beans

Active Member
Everyone here has good ideas. You need to match the cubic footage of your grow space ( in your case, 162.5 cubic feet) with the appropriate fan. A higher cfm fan will enable you to increase the size of your space later without buying another fan, always one of the most expensive purchases. If your venting to a room that's 68 f, it wont be long until the room heats up too...depending on its size.
 
aleksandr2010

aleksandr2010

Active Member
if you dont exhaust your old hot air outside or into an attic then you will never fix the core problem....you can upgrade to the biggest fan on the market wont matter if your just recycleing the same old hot air...If your not exhausting outside your grow is fundamentally fluad from the very beggining.
Click to expand...
I don't know about that; the room i'm venting out into is much bigger than the tent; the heat from inside the tent doesn't warm it up more than 3-4 C...so it sits at 23 C. Warm air rises up and out while my intake for the tent is at the bottom near the floor (where the coldest air should be). I figured if i'm venting the hot air towards the ceiling and sucking colder air in through the bottom of the tent, I should reach a decent temp. My issue is that the outside room STAYS around 20 C while inside the tent it gets up to 35 C. Thats why I figure if i can get more hot air out of the tent I'll be okay. A friend of myn using a stronger fan than me, with a similar tent in a tiny room + venting the same way I am now could keep his temp at below 30 C. Of course, I agree that venting elsewhere is necessary when talking about more than 1 600W lamp
 
FootClan

FootClan

Well-Known Member
aleksandr2010 said:
I don't know about that; the room i'm venting out into is much bigger than the tent; the heat from inside the tent doesn't warm it up more than 3-4 C...so it sits at 23 C. Warm air rises up and out while my intake for the tent is at the bottom near the floor (where the coldest air should be). I figured if i'm venting the hot air towards the ceiling and sucking colder air in through the bottom of the tent, I should reach a decent temp. My issue is that the outside room STAYS around 20 C while inside the tent it gets up to 35 C. Thats why I figure if i can get more hot air out of the tent I'll be okay. A friend of myn using a stronger fan than me, with a similar tent in a tiny room + venting the same way I am now could keep his temp at below 30 C. Of course, I agree that venting elsewhere is necessary when talking about more than 1 600W lamp[/QUOTE

i just dont see how a bigger fan recycling the same old air is going to help much........and why do it wrong when theres clearly a better way(exhausting all air outside).....if you cant exhaust outside then i guess you have to do what you have to do......but i find it hard to beleive you cant exhaust outside i grow in an apartment myself and i exhaust all air outside so it can be done, in the end its what needs to be done... The first thing i think of when i start planning a grow is where will i exhaust outside from this location.......THATS FIRST THING before lights nutes pots soil tents bla bla bla most basic thing that needs to be addressed before anything is " where is my air goin to be exhausted". when i went looking for an apartment i picked one that i know i could exhaust air out of ....... all my friends and every one i know that dosent know anything always worrys about exhaust last....they buy lights and this and that and they set it all up then they say " hmm where should i exhaust the air" im like your just thinking about that now? lol too funny to me....

Like i said if your not exhausting your old air outside then your grow is flaud from the start.........if your buddy isnt exhausting air out then his grow is flaud from the start aswell.....the only acceptable reason to not exhaust your air away from your grow area is because its a "closed loop" system and that means you must have an AIR TIGHT room with Co2 supplement....

not trying to hate on you just beiing real here....and i dont want you to think that what your doing is the proper way...now if you choose to do it anyways thats ok i just want you to know what the proper way is so you can make your own decision based on the facts
Click to expand...
 
aleksandr2010

aleksandr2010

Active Member
I get that you're not trying to hate on me man. I absolutely did think about exhausting air. But in my current situation I found right off the bat there was no way to do it during the winter, which lasts 7-8 months where i am. So i tried to think up another example I witnessed first-hand where someone I know managed to not exhaust any air out of the room and still keep the temp down; and they managed to do it under worse conditions than myn (in a grow tent in a tiny room at 20 C as opposed to my large one); the guy succeeded using a 600W bulb and the only other difference from my system was that his fan was way better. Everything else being the same between me and him, I think if I change the fan I can match him. I totally don't disagree with you that venting air is very important and if i ever go any higher than one 600W bulb I will only do so if my housing situation changes. I gotta improve my situation as much as possible with the resources I have though.
 
You must log in or register to reply here.
Top