Grow room air flow and temp

C

champfire4

New Member
What Strain is it? Indica auto flower.
How Many Plants? 2
Is it in Vegetative or Flowering Stage? Veg/flower
Indoor or Outdoor? Indoor
Soil or Hydro? Hydro
If Hydro, Reservoir size? 25 gallon
If Hydro, Reservoir Temperature? 66
If Hydro, what type of Medium?-Clay
If Hydro, what type of Setup?-Dwc
Size (Wattage) of Light? How Many? 600 hps
Is it Air Cooled? Yes
Temperature of Room/Cabinet? 82-85
RH of Room/Cabinet? 30-40
PH of Medium or Reservoir? 5.8-6.1
Any Pests? No
How Often are you Watering? Twice day 3ml each of pH water
Type and Strength of Fertilizers used? Flora at 740 ppm at (700)
Size or Square Footage of Room? 64 cubic feet 2.5x2.5x8.5
Have blowing 66 degree air from attic through cool tube 500cfm
Out take 100 cfm
Water chiller humidifier 4 small fans
Can not get the temp to stay between 74-78 how can I modify the air flow to achieve this temp
Ideally I would like to have the closet door closed and sealed any suggestions will be aprechiated
 
Is it variable speed? I use the speed adjustment to get the air flowing to get the required Temps. I would also just use the fans to control the air once. Sound like you are using 2 fans to do the job of one.
 
No my big 6" blower can use a controller but did not get one so it is currently 24/7 I am currently modding a 10" fan to fit up top to circulate
 
Something larger than 100 cfm for extraction? Also, can you make you air intake cooler - like from the attic? It would be much easier to keep temp's down with that 66 degree air than the usual mid-70's room temp.
 
Major PITA said:
Something larger than 100 cfm for extraction? Also, can you make you air intake cooler - like from the attic? It would be much easier to keep temp's down with that 66 degree air than the usual mid-70's room temp.
Click to expand...

My goal is to be able to close the door (seal) an maintain 74-78.
Both my outtake an intake run in to the attic both about 4 ft run slight angle going up so I know I have little or no restrictions through the vents.
For the past few days I have been trying different configuration with the vents and blowers. I have 1x 6" 500cfm which ended up rising the temps to the high 80-90 when I blew the cold air in through the cool tube, and vented out using 1x 100 cfm. So I tried a few others but as of now I have the 500cfm sucking through the cool tube and I am using 1x 100cfm and 1x 120cfm to vent out to the attic.
Attic temps are between 62-67 degrees sometimes lower but steady.
I also just added 2x 10" fans one up at the top on high the second low almost at the bottom of bucket but the blades rise above it
About 2 inches. It mainly pulls the air from the bottom and runs it up the side of the wall.
I also have a 6" fan on high connected to the end of my cool tube blowing cold air across the glass. Temps are at 84 with the plastic down door open.
Also running a humidifier in the middle of the sit below the bucket level.
I am assuming the only way to get a stable temp is to actually seal the door to prevent air exchange an create a vaccum not sure though.
 
firstly 84 degrees isnt really a problem in my opinion unless u are having big drips in temps wen the lights go out. big swings in temps will cause more harm than steady warmer temps. i run big rooms and sometimes i really struggle to get the temps down below 80f as AC isnt an option for me. my room temps are always between 78 and 86f. some may argue its too hot but its all about how u adapt to the plants needs. i have fantastic results and if u look thtough my journals u will see what i achieve in my grows.

having said that without using AC the vest way is bigger fan extracting. i never use intake fans asu want negative pressure in the space, main reason being smell leaks. for me its difficult to give an exact answer without seeing your set up as i find it hard to visualise things with just the written numbers.

I grow dwc also and aslong as you can keep your res temps good i dont see you have heat probs at those temps unless you have a real delicate strain. check out my current journal and u will see how i cool my rooms using only extraction.

peace.
 
Seems odd to me.
I use a 440 cfm at about 75% speed to extract air through a 6" cool tube (also using a 600w HPS). I guess the difference is I'm in about 160 cu-ft. Even with the light on I have to add heat to keep temps up during the winter. Air intake is outside air, which is colder than your attic, but with your bigger fan, I'd think you could keep your tent close to the attic temperature if you wanted.
As long as your nutrients are OK for temp' with the chiller, the 85 degrees doesn't sound too bad.
 
Major PITA said:
Seems odd to me.
I use a 440 cfm at about 75% speed to extract air through a 6" cool tube (also using a 600w HPS). I guess the difference is I'm in about 160 cu-ft. Even with the light on I have to add heat to keep temps up during the winter. Air intake is outside air, which is colder than your attic, but with your bigger fan, I'd think you could keep your tent close to the attic temperature if you wanted.
As long as your nutrients are OK for temp' with the chiller, the 85 degrees doesn't sound too bad.
Click to expand...
My RES stay between 64-66 degrees.
My lights are on 24/7 using autos week 5
Have co2 but afraid to use it without being able to control my temps. But it sounds like everyone is saying that 84-88 is not too bad?
Have plenty of negative pressure if I shut the door and put something by the bottom of the door you can hear it slap an stick to the door to seal the leak lol
Can you post pictures here?
 
1451160885766-911283491.jpg
1451160837292-41636652.jpg
 
the way u have ur duct work set up will be causing problem. its acting like a radiator on the room. and because of the bends it wont be cooling effectively. u could try disconecting the cooltube and extract the hot air instead. put ur carbon filter at the height of the room where its at its hottest and have short ductwork.
 
You're room is extremely small and you probably have many bends in your ducting. If you had a larger room that ducting scenario might be ok. Also, you claim that your 6" fan blows out 500 cfm. Negative. I have used a Kestrel velocity meter on a best case scenario 6" fan (simply blowing straight up into an attic with a perfectly tightly stretched 10" duct [yes, you are supposed to have a larger duct than the fan, ask any HVAC professional, although not too large for the cfm capability or else that enlargement works against the airflow] and you will only read 450 cfm @ 65f intake temp.
I will help you solve your problem, but it requires a major overhaul. You will not get the conditions you desire this go round but you will be known as Airos (the potted out Greek god of airflow) on your next run.
Step 1: Learn Basic HVAC theory, specifically how to avoid too much friction (heat) by not using too small of a flex duct. Never assume that a 6" duct pairs well with a 6" fan (10" is the ideal flex duct for a 6" centrifugal)
Step 2: You must learn how to intake air from the highest point of your structure while sealing out all airflow from low points of the structure. The air is slightly cooler at the second floor but the most important side benefit as that there is no spider mite dander up there. That stuff doesn't float around the second floor air space surrounding a house.
Step 3: Geothermal Cooling (if you are growing in a basement that is unfinished with concrete block walls and cement floors exposed). If the air takes an extremely long path down from the second floor and around the grow room (making maximum contact with cool basement floors and walls) you will find that your intake air is 4f-6f cooler than the temperature of the air right outside the front door of your house.
Step 4: Cool Tubes??? Nope! It does not work as efficiently as having the intake air come in from the top side wall of the grow room while getting sucked out by equidistant precisely cut holes in a foam ceiling. This creates a jet stream above the light that heat naturally flows toward like a magnet. Practice these 4 steps and get a nice bat wing style reflector and enjoy cooler temps while getting better light reflection (cool tube are not the ideal for light reflection)
Step5: Imagine a 600 watt light in a 5 gallon bucket. Gonna get real hot! Imagine the same light by itself in huge open basement. Chart an x/y axis of space (cubic feet) and lumens (heat being the line on the graph itself). Figure out where your closet falls into place on this graph.
After going through the 5 steps, we arrive at our conclusion when we recount Step 5. You have no choice but to get an AC for that small space if there is no way of improving all of steps 1-4 and you can't let go of the 600 watt light.

Small spaces require way more cfm per cu.ft for the proportional amount of lumens used in a larger space because the walls (and all the objects within) retain so much more heat and most importantly the inverse square rule of lighting applies proportionately to heat retention of the air just the same as lumen distribution.
Or you could just down grade to a 400 watt right now and you will probably get better results than struggling with high temps and a 600 watt.

With intake air coming in at 45f I know a little birdie that runs 3600 watts of hps with just a 6". Of course that little birdy has a temp controller that add more fans as the temp climbs. A boat load of dampers, thermostats and give or take 300+ ice cube relays!!!! Yeah, that birdie doesn't trust PLC's.
 
champfire4 said:
1451160867533320893575.jpg
14511607571491231814099.jpg
1451160850819-886385539.jpg
Click to expand...

Still can not achieve 74-78 degrees or close the door maybe another 6" blower for the attic air instead of using 2 4" blowers to bring the attic air in maybe 400cfm instead of using total 220cfm with 2 fans
I should have plenty of cfm now, just don't know how to correctly arrange the fans, vents, ect. Any experience in this area will be greatful.
 
Well turned off 5 fans inside the growing space temps are staying at 82 degrees so I guess those fans we're doing nothing hmmmmmm
 

Similar threads

B
A little help with plants that could be doing better
2
Replies
37
Views
3K
Kriaze
Kriaze
D
ph up alternatives?
Replies
11
Views
6K
devils letuce
devils letuce
2
Please Help First Grow
Replies
2
Views
1K
Pigeons420
Pigeons420
D
drooping after lights out
Replies
9
Views
1K
labexperiment
labexperiment
S
Help diagnosing
Replies
13
Views
2K
Mountainman80
Mountainman80
Back
Top Bottom