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AC wont shut off

vein5

Member
My room is 5x10x8 with 2 bare stacked 600's hanging vertically. The exhaust for the whole grow room goes into my central air return with a 10 in scrubber. The out and intake from the air conditioner come from the outside like a window unit so the hot air from the air condition go out the window. My unit is 1100btu's and wont shut off. I guess what I'm asking should the whole room exhaust be on low or high. If its on high won't it just suck the cold air out of the room. How do you guys do it.
 

Jnugg

Active member
Veteran
1100 or 11000 BTU's cause 1100 wouldn't even keep me cool while on the shitter,let alone drop room temp noticeably....maybe that's why it runs constantly...too small.
 

STUNKY

Member
That's what I was thinking 1100 ain't shit.. Does ur room ever cool down to the temp the ac is set on?what temp do u have it set on?
 

Galactic

Member
you're not really clear yourself if you are running a sealed room or not...

does it get hotter if you dont run the whole room exhaust? is that why you continue to use it?
 
T

TribalSeeds

Shit I worry about the cracks under the doors letting too much AC air out.
 

Bigge

Member
Vein- I run a similar setup...except I vent filtered exhaust out the window along with the dual hoses from the portable AC.

Three parts to this answer.

1. Room air refresh rate. What is of primary importance from an exhaust perspective is air circulation to get fresh CO2 to the plants....calculate your needed air flow to replace all air in the room in a few minutes...some say 1 or 2 min to exchange room air...see ventilation post on this site (https://www.icmag.com/ic/showthread.php?threadid=112862) for more info and that should answer you question on how high your exhaust rate should be. I exhaust my 4x8 at 675 Cfm...I would call this a high exhaust rate and think you would need similar.

2. How to keep your cooled air in the room. Once you figure out the needed exhaust rate in cubic feet per minute then you have to prevent exhausting your cool fresh air. The intake for AC cooled air should be near the ground and preferably as far away from yhe exhaust as possible. The exhaust from the room should be positioned as high in the room as possible - preferably near the ceiling- to endure you are exhausting the lighter hotter air and not the cooler heavier fresh CO2 rich air. Keep in mind that with your setup you are exhausting from the room and you will need to be in taking air also...this will come from the Centrally cooled rest of the house and means the room can't be air tight.

3. Controlling the AC. As for the AC not turning off...you could use a temp controlled power plug so if it gets to cold it can turn off the AC if you must have it automated, but as the others said 1100BTU unit can probablly just run constantly during lights on and maintain 75-80 degrees only with two lights on (depending on the room size...1100BTU is good for 10x10 room depending on intake temps. So your 5x10 should be fine with 1100BTU...I run a 4x8 tent). A better less expensive thing would be to just put the AC on a timer like the lights to come on right before the lights and go off right after the lights. In my setup I plugged the AC into a plug controlled by the light switch so I manually turn it off or on as needed because sometimes for me the AC isn't needed....when I go out of town I put the AC on a timer.

Hope this helps...good luck.
 

vein5

Member
It was a mistype, i have never seen a 1100btu air conditioner. Its a 11000btu AC. My room is not sealed and i cant keep the temps down. My electric bill last year was $400-$500 a month bc the air from my house was just being pushed into the attic to outside, so my central ac never shut off. Now this year i am going into the return so no air from the house is pushed into the attic, and I have this portable ac to help. Even with my 8in blower on high the temps stay around 90 when I have no ac going.
 

vein5

Member
I figure if the exhaust is on high the ac could never keep up, and the cold air would just be pushed outside. My exhaust is right above the lights on the ceiling so that good.
 

Ez Rider

Active member
Veteran
Your exhaust and your a/c are playing tug-o-war 24/7. This is why the bills are so high. The a/c will not work properly until you seal the room. An 11,000BTU a/c should be able to handle the heat from 2x600w and then some. Assuming your ballasts are in the room, and you're not air-cooled, your lights and ballasts are adding ~7000 BTU/hr to your room. Unless you live somewhere incredibly hot, the other 4K BTU/hr should handle any ambient heat issues in a room as small as yours. If you do seal the room, you'll need a dehumidifier for the dark cycle, or you'll need to exhaust. If functioning properly the a/c should handle the RH when the lights are on.
 

Bigge

Member
Regardless of the hood type...You should figure out another intake source because the exhaust air must be replaced from somewhere...create a lung room with air from outside that is not centrally cooled or I've seen people vent the room under the house and intake from there (they run lights at night so intake is nighttime cool air)...if its cool enough where you are and you go the outside air intake route...you should filter incoming air with a micron filter..intake hole will need to accomadate the cfm of the exhaust...especially if you at running 8" exhaust fan. There are some good posts here on lung rooms, intake hole sizing and active vs passive intakes. Depending on where you pull your intake from relative humidity can become a concern...make sure it's not air that is bad for your garden that you are intaking. I once ducted intake from near a dryer exhaust and the air would drop to really low RH which sucked all the moisture from my vegging plants.

Good Luck
 

Bigge

Member
EZ is also right..you could seal it off...it would require CO2 gear(~300 Bucks min used) at the very least...then you have to change CO2 bottles.....

Or if not going the sealed route (i dont like having to change co2 and don't always have access to CO2).... just use passive or active intake and duct your intake air from somewhere not cooled with central air.
 

Granger2

Active member
Veteran
I'm not quite sure I understand your set up. Window units and thru the wall units don't exhaust room air, and don't intake outside air. They have 2 closed systems. Outside air is taken in to cool the coils and exhausted back out. On the inside, room air is drawn in, cooled, and blown back into the room.

Turn off the 8" fan, seal your room, buy a CO2 tank and regulator, and you'll pay for it quickly with electricity savings. You can carry your tank from the house to the car in a box or suitcase to get it refilled, and the neighbors won't see it. Your wallet will be fatter, your room will be cooler, and your AC will last longer. Also, you won't be intaking fungal spores, and you can control humidity. Good luck. -granger
 

vein5

Member
Yeah I was up early and tore my fans out, sealed up all holes , hooked up my dehuidity, filled my co2 tank, and bought a titan co2 control. Since my lights are on at night it was a total pain in the ass doing this in the dark with my green light. Thanks everyone for helping me out
 

vein5

Member
I just hope my c99s were not destubed by a little light going in and out since they are 5 weeks into flower.
 

Sativa Dragon

Active member
Veteran
I'm not quite sure I understand your set up. Window units and thru the wall units don't exhaust room air, and don't intake outside air. They have 2 closed systems. Outside air is taken in to cool the coils and exhausted back out. On the inside, room air is drawn in, cooled, and blown back into the room.

Turn off the 8" fan, seal your room, buy a CO2 tank and regulator, and you'll pay for it quickly with electricity savings. You can carry your tank from the house to the car in a box or suitcase to get it refilled, and the neighbors won't see it. Your wallet will be fatter, your room will be cooler, and your AC will last longer. Also, you won't be intaking fungal spores, and you can control humidity. Good luck. -granger

^^ THIS ALL THE WAY ^^
 

Bigge

Member
Nice....did you seal electricity outlets...proper seal is a pain in the ass...keep in mind that CO2 is heavier than air and will fall...keeping the seal means less CO2 refills and the electricity outlets are holes into your walls which can suck in lots of humid CO2 rich air if there is any pressure difference between the room and the house...got mildew on the walls of a house by not doing this.

Safety- additionally CO2 rich air can kill sleeping humans...don't put the sealed grow room over your bedroom unless its good and sealed...I'd suggest co2 monitors in bedrooms especially if you have kids...

Smell- You do have a dual hose portable AC right? Single hose units can pull in air...which causes positive pressure on the room and pushes smell and CO2 out of the room..

Mildew-You should keep an exhaust fan setup...IMO exhausting the room daily reduces chances for mold/mildew....and if your not burning sulfur then mildew can be a problem when sealed....especially if it gets in the paint...you can get mildew resistantaint paint...ounce of prevention works wonders.

Sorry if you know this already..,..sativa high gives me OCD.

Chem99 (at least my runs with it) was pretty stress resistant so hopefully your mission today was harmless....going with a batch of Chem99 and Gorilla glue next....I'm on week 4 flower with Platinum Cookies and GSC now.
 

vein5

Member
Well my titan control says my house has 1000ppm naturally, maybe its because im near the city where its heavily populated so more co2. I dropped $600 on the control and it says factory calibrated. The only outlet is on the ceiling which was a light before. I have no exhaust but keep the humidity in check. Wont a exhaust just be another way for cold air and co2 to escape even when not running? My ac still runs alot but i know I sealed everything right. I am in maintenance and remodeling so I am pretty handy.
 
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