In room ac unit

I am looking at using an in-room ac unit to help keep temps down in hot summer. I am looking at a dual hose model. It has an it has an intake hose and exhaust hose. It comes with a window kit to hook up hoses too. The exhaust needs to be hooked up to get the heat out of the room. But would it be better to let it use the intake inside the room as the outside temps will be 110°+? If it uses the cooler room air would it not run more efficiently?

Looking at this model but cant find an Amazon link: Whynter’s Elite ARC-122DS

I like this - it does not have an attachment that allows intake hose. Pulls air in through vent in the back condenses it and exhausts heat out of a hose that runs outside tent. Works really well. On amazon for I think 315 but they have a smaller model as well for 250

I grow in attic in southeast us - attic temps are consistently 100-120F and it maintains tent to 69 without an issue


@Sirsmokesalot So you have it inside the tent?

I sure do let me see if I have a pic


Ha ha I just totally got an education in this.

My room used to be unsealed, just bare plywood walls butted up to each other.

I wasn’t using any kind of intake hose for over a year then I decided to insulate my room and I sealed it off completely with a two part spray foam.

My humidity skyrocketed to over 80%. Took me awhile to figure out I needed to bring in some outside air and it works well now

I had to modify my AC to where it would work like a two hose.

I had two cover all the intake vents with buckets then run ducting to those buckets.

Your idea will probably work as long as the room your using it in has some air infiltration but the unit will work most efficiently if both hoses are hooked up


I like the one you want to go w @Sirsmokesalot May I ask u if this is a solution as well or do u feel the one you are using is goon enough? The set up will be 4x8 idk the height yet but more than likely 8ft I don’t mind running exhaust out but I see that this one takes air in the room (hot) and converts it to cool air which serves a dual purpose there, as well as a dehum. Really just asking your opinion

@Countryboyjvd1971 can explain it better than I can since he is a HVAC guy by trade but you will need to exhaust outside of grow area. If not you will constantly be fighting a losing battle as it takes energy (with a product of heat) to cool the air. So if you did not you would be cooling the hot air you just exhausted and the cycle would continue constantly wasting energy and your temps would maintain a higher degree than I would like personally.

Like @TDubWilly said it helps to also have intake bring cool air in - for my setup I have a 315 cfm fan bringing in 69 degree air from my livable space in my house to the tent that has the a/c in it. Helps maintain ambient temps. His is a bit different since I’m sure he wanted to max out his space but is essentially the same concept.

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So sorry I forgot to explain it all to get a warranted answer well I will be bringing in outside air lol naturally filtered of course through hepa but the outside air I have set up pulls air out of tent by doing this it is also pulling air in in through the hepa like an open loop hybrid where air is exhausted out but pulling in the new air with that being said it wouldn’t be recycling but the air I bring in so is this better explain it and make this sufficient @Sirsmokesalot @TDubWilly

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So for my instance I would be better to just use the in house ac air at 80° instead of bringing in outside air which is 110° for the input side? So in theory I could put inside the tent or just inside the room to cool the room,11 x 13’total room. and the carbon exhaust filter in the tent would suck in the cooler air from the room?

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Says it cools up to 400 sq ft, it’d probably do fine outside the tent.

Edit: I’m not a HVAC guy, but a refrigeration guy…same doodoo, different smell.


All air conditioners are different

Window units and two hose stand alone systems work in similar fashion…

But work differently than a one hose system…

And all of these obviously work different than a mini split or central air…

Three different setups above. In order to choose the right one for you, you have to know how each one works and how your grow space works.

I promise this is the BIGGEST THING that you need to know in order to choose the right one…is there air infiltrating your grow space or not?

If you can answer that question then you can begin to figure out which system is for you


Ok my room is 11 x 13’ and the tent is 4 x 8’. So I will get the dual hose I showed in the first post and vent the ac out to outside and just keep the intake hose and keep it in the room. I have the 6" fan with carbon filter for the tent and I will vent it to the outside also. Then I can close the door to the main room and with the house AC going and the room ac going I should be able to control temps a lot better. The carbon filter exhaust would pull air into tent from the cooled room.I am thinking the room ac unit would only need to run on the 12/12 cycle with the lights so it should not be too bad on $$.

Does this sound reasonable?

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If your running it in your house where there is already central air, and exhausting the hot air outside, a one hose system, two hose system, or a window unit should do great for you.

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I almost think I know how the 1 hose and 2 hose versions work. If I had the 2 hose and took the intake hosed and put it in the tent through a ventilation hole and used the tent air it would be using warmer air from the tent to cool the room and then the cooler air would get sucked back in through the tent ventilation screens cooling the tent.

Does that make sense?

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I think you’ll be sending unfiltered air straight outside and it will smell around your house in flower. Plus, if you have any other exhaust fans in the tent then the AC intake has to fight those to get air and the AC won’t work as well as it should.

This is a problem with the one hose unit as well.

When the intake is bringing in fresh air from outside then that same air is what gets exhausted.

When the intake is bringing in air that wreaks of cannabis, then that same air too is what gets exhausted.


That makes perfect sense. I am just worried about the outside air being 115°. But it seems that would still be my best choice

Ok so this is my set up here I have an 10.10.10 gorilla unit. I have it set up to exhaust co2 at 20-30 min rate all this is set up through a charcoal filter w fan exhausting the air from top. opposite side cross corner I a hepa filter for the air that is being brought in through the exhaustion this is my loop system and if I left out info I will add but giving a basic description now in this scenario @TDubWilly which u it would I be better with the on I originally posted or what basically a 1oo sq ft tent 1000 cubic inside hps 1000w 4 as I will only be using a 4-4x4 W walkway crossing. Will the unit I originally posted work in this scenario due to the fact that I would be bringing in new air?

As for your question is there air infiltrating the system I’d say no besides the air I’m bringing in and co2

@RAP if u want to fun it like that the 2 hose system u have to start looking at option such as ozone to treat the room outside and then u could utilize that system I’d also link it w a filter kind of much though for the circumstances rather just get the right unit ya know but I do understand sometimes you got to do what you got to do

You could even close the loop and scrub the air wouldn’t this would work as well.

If you have zero air infiltration then you can’t use a one hose system but I bet you have more air infiltration than what you think.

Think of a bank vault that has no air coming in at all. If you put a one hose system in there then all that machine will do is exhaust and no air will be in the room for the machine to intake. On the two hose systems the second hose is an intake allowing it to get air from elsewhere.

I straight can’t think of two many scenarios where a two hose system won’t work, same with a window unit.