This Ain't Ya Daddys AC Box!!!

[hoosierdaddy]

midwestnug, I am honored by you using my AC sketch, but as often happens when we use others material, without referencing a link, it often gets things out of context. As is the case here.

OgreSeeker, as you mentioned, there should be more air flow than what the sketch shows, and if the rest of the thread were shown, you would see that what you described is exactly what I have with this set-up.

As you can see, there are divisions in the air flow areas.
This unit works at full, or better efficiency. I say better because I am pulling on the exhaust air in addition to what the AC unit fan is doing.
The air that enters the unit is fresh ambient air that has been in the veg chamber. The cold air that is created is separated from the ambient air intake, and only the air that is in the flower chamber gets recirculated through the cooler. None of the cool air gets used to blow through the exhaust.
Here is the rest of my cab AC thread if anyone is interested:
Hoosierdaddy's Cab AC
BTW folks,
I do not use wood and glue/nails. I use insulation board and Gorilla duct tape, which I would think to be much easier than even the corrugated plastic used in this DIY. Dow Supertuff R is the easiest to work with and most versatile product I have used since starting this cab venture.

DigitalHippy,
I don't know how you can make such blanket statements? Maybe you should be specific in what you are saying, because I think you may be just spouting your opinion off with no sort of physics backup.
The man already saw that he was not running to full efficiency and had to add a fan to the intake. This should, and probably did, make up for the restrictions he made in the air flow.
I see no problems at all with the exhaust side of things.
But then maybe you are seeing something I don't...be specific so we can see why his unit won't work like it should.

 

[Guest 18340]

hoosierdaddy, what size/cfm fan are you using to suck the heat off the back of your ac unit?

 

[hoosierdaddy]

evlme2, The AC exhaust ducts to the cab exhaust chamber on top. This chamber, which also houses the ballasts, takes both the air from the AC unit and the cycling air from the flower chamber through scrubber and 6" ducting, out the top, and through the ceiling, powered by a Stanley blower that I have in the attic.

* The AC would work fine even if I wasn't pulling on the exhaust air. The unit has a fan pushing air through the heated coils, and as long as the air flow past the coils is not restricted, the fan itself provides all that is needed to carry the heat away, as designed.
The fact that the fan in the attic is pulling a bit more at the exhaust air than it would normally just lets the unit not have to work as hard. It also helps to keep the condensation level down, as it evaporates the water while the unit is off. My small unit has no drain at all, and I am turkey basting about an ounce out every day or two.
When the RH is down, the unit will create a bit of water during lights on, and the fan pulling through it during off time gets the thing bone dry again.

 

[midwestnug]

I only showed the 1 pic hoosier cause thats all i did with my setup and i was trying to explain how mine was set up not yours... u just happen to have the best pic i could find... sorry if u didnt like me using it!... anyways my air cond is just like the pic shows with the side and top vents in the grow room and the box is around the back, the back is then attached to my window box. (note) i have a window fan in the box to help exaust the window box... there is no hot air whatsoever comming out of the side and top vents in my room, its pure cold aiir and its having no problems keepin my room at 79 degrees on its lowest setting, and its only an $88 air cond from walmart 5050btu. since i hooked it up my humidity has went from %62 down to mid 40's. I know its apparently not setup like u guys run yours but it seems to be doin a great job. i even use the drain bucket to rinse my utinsels, lol

 

[hoosierdaddy]

No, nug...I was sincerely honored. I just think it best to reference things to keep confusion, and wasted ASCII, to a min.

Your setup is going to work. And it is basically what this threads DIY does, save for you are not isolating your incoming air that is used to cool the heated coils.
As is, you are using the air that you are cooling to also help cool the heated coils. This is a very big loss of efficiency. If you can figure out how to bring in a separate air supply, like this DIY does, then you will have a beauty system that will last a while.

 

[midwestnug]

so if i brought in a separate air supply rather than from in my room, would it still dehumidify my room? if its not getting its air from in the room how is it gonna dehumidfy it?

 

[OgreSeeker]

midwestnug, I am honored by you using my AC sketch, but as often happens when we use others material, without referencing a link, it often gets things out of context. As is the case here.

OgreSeeker, as you mentioned, there should be more air flow than what the sketch shows, and if the rest of the thread were shown, you would see that what you described is exactly what I have with this set-up.

As you can see, there are divisions in the air flow areas.
This unit works at full, or better efficiency. I say better because I am pulling on the exhaust air in addition to what the AC unit fan is doing.
The air that enters the unit is fresh ambient air that has been in the veg chamber. The cold air that is created is separated from the ambient air intake, and only the air that is in the flower chamber gets recirculated through the cooler. None of the cool air gets used to blow through the exhaust.
Here is the rest of my cab AC thread if anyone is interested:
Hoosierdaddy's Cab AC
BTW folks,
I do not use wood and glue/nails. I use insulation board and Gorilla duct tape, which I would think to be much easier than even the corrugated plastic used in this DIY. Dow Supertuff R is the easiest to work with and most versatile product I have used since starting this cab venture.

DigitalHippy,
I don't know how you can make such blanket statements? Maybe you should be specific in what you are saying, because I think you may be just spouting your opinion off with no sort of physics backup.
The man already saw that he was not running to full efficiency and had to add a fan to the intake. This should, and probably did, make up for the restrictions he made in the air flow.
I see no problems at all with the exhaust side of things.
But then maybe you are seeing something I don't...be specific so we can see why his unit won't work like it should.

Good post and thanks for clearing that up. I was starting to doubt myself even though I knew better. I'm no ac tech so I listen carefully to other opinions on this.

hoosierdaddy, what size/cfm fan are you using to suck the heat off the back of your ac unit?

Most ac boxes work well with a 6" inline fan. I would prefer either a 6" high output or an 8" in mine just to be sure. Your trying to avoid heat build up in the box...that's all.

I only showed the 1 pic hoosier cause thats all i did with my setup and i was trying to explain how mine was set up not yours... u just happen to have the best pic i could find... sorry if u didnt like me using it!... anyways my air cond is just like the pic shows with the side and top vents in the grow room and the box is around the back, the back is then attached to my window box. (note) i have a window fan in the box to help exaust the window box... there is no hot air whatsoever comming out of the side and top vents in my room, its pure cold aiir and its having no problems keepin my room at 79 degrees on its lowest setting, and its only an $88 air cond from walmart 5050btu. since i hooked it up my humidity has went from %62 down to mid 40's. I know its apparently not setup like u guys run yours but it seems to be doin a great job. i even use the drain bucket to rinse my utinsels, lol

Ok I understand now. You are indeed using air conditioned air to cool your ac. This is VERY VERY inefficient. You would be much better off connecting an input duct with an inline fan sucking air from outside the room through and out the back of the unit. Bet you'll save some $$ on your electric and add some years to your unit if you do it this way.
A 6" canfan running constantly cost much less than an ac that stays running for long periods of time.
Let me ask you this...does your ac compressor kick on and off alot or does it run continuously?

so if i brought in a separate air supply rather than from in my room, would it still dehumidify my room? if its not getting its air from in the room how is it gonna dehumidfy it?

Yes it will still dehumidify the room. Here's a good explanation I found posted on DigitalHippys ac box thread. It's a post by "ItsGrowTime" and it helped me understand a little better...
-Hope you don't mind DH and IGT-

"The exact workings differ a bit from model to model but maybe I can help you understand a bit better. Inside a window AC, there are two fans, a compressor and coils. One fan pulls in room air and runs it over the cold part of the coils to cool it (by removing the heat from the air) and blows the now cool air back into the room. A second fan pulls outside air (from the top rear usually) over the hot part of the coils (removing the captured heat) and blows that air back outside. There is no air exchange between the outside and inside air and if designed properly, they should never come in contact. The dehumidifier portion works because hotter air holds more moisture than cooler air. When the air is cooled, the moisture (humidity) turns to water. Same principle as why it rains when a cold front comes through your area."



Think about it like this...
when you install a window ac into a window, only the front end is sticking into your room. The rest of the unit is outside but it still dehumidifies the room. Same principle applies here.

 

[midwestnug]

well the weird thing is, my ac barely runs. but it hasnt got too seriously hot outside yet either so i might b in trouble come august. if i start to have problems i can always modify it pretty easily using to system in this thread. but i still dont understand how it dehumidify's the air in the room if its not getting its air from that room...

 

[TheOneWill]

Can you take a 400watt light and suck the air from it with the a/c unit?
But cool the air in the area.

 

[007grow]

Here is how I did mine.

I run dual 12k btu units, had to modify them so they don't spit out smelly air.

tools
wire cutters
tin snips

materials
2 x 4"x12"x6"duct registers $7ea
sheet of hvac metal $8
aluminum tape $7

Here is a pic of the unit. notice the lower left hand portion of the picture I started cutting the cooling vent to reduce restriction.


Here is another pic, so you can get a better idea.


after everything is cut


This is the baffle I made just your normal 4" x 12" x 6"duct register...
I then cut a piece of sheet metal so I could make it have an opening to match up, bent it up and used aluminum tape to seal it up
I looked for fucking corrugated plastic and all they had was for sale signs like that and buying the hvac metal sheet at lowes was only like $8 so it was cheaper and a better solution since I had tin snips at home


About to attach


Look inside notice the notch at the back to clear the wheel I will be caulking this whole thing on and using aluminum tape to secure it while it dries...


Here they are prior to hooking up

 

[007grow]

I saw a 24k-btu 220v window unit for only $399 at lowes today thats pretty cheap, lucky for me I paid only $150 for one of the units I have and the other was a gift.

 

[impeachme2]

Where does the water go in most smaller window A/C units? Do they just puddle in the back to be drained or is there a drain line?

 

[OgreSeeker]

EDIT

 

[impeachme2]

Doing that would be extremely helpful with maintaining the amount of water in a res. Most of the water that is used by plants is transpired, then condensed to liquid by the A/C. Very little water remains in plant tissue compared to the amount that is transpired.

 

[Hempster]

well the weird thing is, my ac barely runs. but it hasnt got too seriously hot outside yet either so i might b in trouble come august. if i start to have problems i can always modify it pretty easily using to system in this thread. but i still dont understand how it dehumidify's the air in the room if its not getting its air from that room...

I'll jump in here and give it a shot. Like someone said and Ogre quoted, there are two fans, a compressor, and coils. But there are actually two separate coils: the evaporator coil (cold) on the inside, and the condenser coil (hot) on the outside. Ideally, the two systems are completely separated from each other in terms of air flow, air supply. The evaporator coil should suck air from the room through its intake grill, pass that air through the cold coil where the condensation occurs (thereby dehumidifying), and blow the cold air back into the room through its discharge grill. Those two grills are both on the inside front face of the unit. The other fan sucks in outdoor air, blows it through the hot condenser coil, and discharges it back outside. What you're doing by having the condenser intake use room air is like leaving the door open. Actually, it's like having a six inch duct with an inline fan in it blowing hot humid outdoor air into your room the whole time your AC is running! The air going out your hot discharge has to come from somewhere. It's being made up by air leaking into your room through whatever little cracks there are. I wouldn't wait for the hot days of August--I'd get that other duct set up now, because it's wasting a lot of money. Is this making any sense? This is why the single-duct portables are such a bad design. I actually bought one recently from the local job-lot store because it was all that was available locally and I was desperate. I'll return it as soon as my dual-duct unit arrives from Costco (which I may also return, later, if I decide on a mini-split, or one of these ducted rigs y'all are doing). So if you use only outdoor air for the supply and exhaust of the condenser coil, you will not only get better air conditioning, you will also get better dehumidifying, and less $.

Hempster

 

[OgreSeeker]

EDIT

 

[hoosierdaddy]

Not sure why, but the system is not letting me post up new shots...
I will try to explain what I was saying best I can...

The AC unit in the picture has vents on the top and three sides for the fresh air intake that cools the condenser coils. The internal AC fan is pulling air through those vents, and the CFM at which it does this is determined by both the power of the fan, and the size of the opening it is pulling air through.

What he has done is eliminated ~2/3 of the air intake area when he taped up the top and one side vent. That leaves only the one side vent to take in all the air. And yes, the additional fan will be pulling air through the unit, but again we are back to the restricted air flow issue. Since he is restricting the original air flow by 2/3's, which now dictates he needs an additional fan source to get enough air moving.

If you look at the vent, it is half covered up by vent metal. If you were to snip all the vents out of the rectangle, and make one big hollow square out of it, you would have added nearly twice as much room for air to flow through as it was with the vent intact.
See what I'm sayin???
Even though you have a fan added to pull air, it will perform at a higher CFM the more intake opening area you give it. Thus, the better (cooler) it will run, with less strain on the fans.

It ALL, and I mean just about every AC issue, deals with the air flow and how it is manipulated. Choke it down and you start to degrade efficiency. Open it up and increase efficiency.

*EDIT:
This has nothing to do with the cool air side of things. When you open up the vent (cut the vent metal out), it will still have the duct fixed back to it as it is now.

 

[lotowork777]

Thank you for the AC idea.

 

[Green Force]

some one prolly already put this btw pull enough air from any a/c box and you will not get a drip i have a 2'x2'x2' 6,000 btu a/c box with a vortex 6" fan pulling the air and i have not had a drip yet but i did hook up the drip tube and put a hole in the bottom of the box with a rubbermaid underneath it will drip when i turn it off btw its always on =P

 

[hoosierdaddy]

The drip will be in relationship to how much relative humidity is in the air.
When the RH is above 70-80% it is going to be hard to keep the water from condensing even with the air from a 6" going through.

At 65% and below, my 5050btus runs bone dry with a 6" exhaust. 75% and above and I can expect an ounce or four per day.