What Ac what y’all Recommend

Cesar300_

Member
Hi growing brothas I’m wondering what Ac would y’all recommend for a 15 by 15 living room . I will be running 12 315 watt sun systems growing lights . Currently using 3 fans . Highest Temperatures I’ve recorded were like in the 85 range, definitely too hot for them . Also using a 10 inch intake fan
 

Renfro

Well-Known Member
Well first off, if you run an AC you will want to stop running the blowers except for a periodic vent to bring in co2 unless you are using supplemental CO2. You will also probably need a dehumidifier when the lights are off or a controller that will run the blower to remove excess humidity.

Now that we have all that out of the way... on to your question. A 14,000 BTU/hr unit may do the job, not 100% though as I have no experience with the 315w fixtures. I hear they run a lot cooler than HPS. With HPS I would use a 2 ton (24k BTU/hr) for that much wattage. My safe bet is 1.5 tons.

Perhaps someone around here that is running several 315's can tell us how much AC they need to use.
 

Renfro

Well-Known Member
I have heard a guy say he had 4000 watts of DE CMH in a room and he cooled it with 20k BTU. I don't know how the 315's compare to the DE 1kW or 630 watt bulbs, if the heat scales up in linear proportion to the wattage. I do know that my 1kW DE CMH lights do seem to run a little cooler than HPS, just not exactly sure how much cooler. For you 18k BTU/hr may be just enough.

So at 18k you are beyond most portables since thats 240v territory. Window shaker or mini split?
 

TacoMac

Well-Known Member
If you're only hitting 85 degrees it won't take much. About 8000 btu of AC would be more than enough.

Ignore all the other shit. It's irrelevant.
 

Renfro

Well-Known Member
If you're only hitting 85 degrees it won't take much. About 8000 btu of AC would be more than enough.

Ignore all the other shit. It's irrelevant.
Well I think he is venting pretty hard and hitting 85. You still think that when he stops venting to run AC that 8k will do it? 8k BTU/hr to handle the total heat load from 12 x 315?
 

TacoMac

Well-Known Member
Well I think he is venting pretty hard and hitting 85. You still think that when he stops venting to run AC that 8k will do it? 8k BTU/hr to handle the total heat load from 12 x 315?
Yes.

He's not venting "pretty hard". He's using a single 10 inch fan. I wouldn't call that "very hard" at all. It is, in most circles, considered minimalist.

Just add the 8000 btu window AC unit. No need to touch anything else. It'll be fine. Should be able to drop the top temperature down to 78 to 80 degrees with relative ease. I have one cooling off a 900 square foot basement area. I'm sure one will be more than enough to handle his paltry 225 square feet especially given that he's running CMH lighting.

Edit to add link: https://www.walmart.com/ip/GE-8-000-BTU-Window-AC-With-Remote-AEW08LY/661762867?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227274624905&wl0=&wl1=g&wl2=c&wl3=329492463739&wl4=pla-625182676951&wl5=9010767&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=online&wl12=661762867&veh=sem&gclid=EAIaIQobChMIpKnLxtrr4wIVxJ-zCh3d6A_yEAQYASABEgKy8PD_BwE
 

Renfro

Well-Known Member
He's not venting "pretty hard". He's using a single 10 inch fan. I wouldn't call that "very hard" at all. It is, in most circles, considered minimalist.
Currently using 3 fans . Highest Temperatures I’ve recorded were like in the 85 range, definitely too hot for them . Also using a 10 inch intake fan
I was thinking 3 exhaust and one intake?
225 square feet especially given that he's running CMH lighting.
Well it's definitely more about the heat from the lighting than the square footage and he is running 12 lights. I don't know that he is gonna cool 3780 watts with 8k BTU/hr. I think the low number would be one ton and thats too low IMO. Lets go by the BTU / watts equivalent of 3.412142 watts per 1 BTU/hr, multiply that by 3780 = 12898 BTU/hr. Now I haven't met a HID light yet that only put out 3.4 BTU/hr, I haven't run 315's though. Also we have to factor in other heat loads whatever they may be. I personally think 1.5 tons (18,000 BTU/hr) is the good bet but minimum 14,000 BTU/hr.

I would have to hear from someone that is actually running 12 of the 315's and cooling it with less than 13k BTU/hr.
 

Digger47

Well-Known Member
If money is no object, yes. They're typically 3 to 5 times as expensive as a simple window AC unit.
I paid 700 for 12k with heat and it came with the lines. Parents just bought 24k daikin for 1300, just ac. Gonna pay on one end or the other
 

Renfro

Well-Known Member
Thing is though, a good minisplit is a great luxury and it is a world of you get what you pay for. So if budget allows I would definitely go minisplit and I would go with a 2 ton unit just in case I decide to add more heat like a CO2 generator or more lights.
 

TacoMac

Well-Known Member
I paid 700 for 12k with heat and it came with the lines. Parents just bought 24k daikin for 1300, just ac. Gonna pay on one end or the other
Like I said, if money is no object, yes. Fact is, he can cure his problem for 200 bucks. If he has the 700 dollars (3.5 times the amount) or the 1300 dollars (6.5 times the amount) to blow, sure. He'd be better off going that route.

On top of mini splits don't vent the smell.
Nor do window units. They draw air from the inside and return it to the inside. The air from outside cools the compressor unit.
 

Digger47

Well-Known Member
Like I said, if money is no object, yes. Fact is, he can cure his problem for 200 bucks. If he has the 700 dollars (3.5 times the amount) or the 1300 dollars (6.5 times the amount) to blow, sure. He'd be better off going that route.
You can pay up front with a mini split or you're gonna pay for it with electricity. Of course do what your budget allows, but mini split is a better choice.
 

Renfro

Well-Known Member
Seeing as it's a living room I suspect it's probably above grade thus a solar heat load is also applicable. So J manual calculations would dictate some additional BTU for summer heat depending on what climate zone he lives in. So 13k BTU being minimum for the lights IMO, plus whatever number a J manual calc would provide is what he needs. So oversizing the unit is a simple solution and using a minisplit he will have the benifit of the system being able to run just as hard is it needs to maintain temps instead of just being on or off with no in between. This will reduce temp swings, eliminate short cycling and provide better energy efficiency. He can also run when it's cold out with a low ambient rated unit.
 

Renfro

Well-Known Member
With a descent 2 ton minisplit properly installed I guarantee that he will be happy. Anything short of that and I wouldn't be recommending it as unhappiness is probable IMO.
 
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