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Calculating The Size of a Air Conditioner

Chewwy

Member
Help cooling a sealed room

Help cooling a sealed room

Got a few questions on how I should cool my sealed room...

My room is in the lower level of a building (basement),the room was originally used as a cold storage room.the room is built into the side of a hill and gets no direct sunlight.

The room is 10' x 15' x 10',with an adjoining room appx about 10' x 5'

Do I need to go with a mini split system or could I use a portable unit or window unit vented into the adjoining room?(adjoining room is also sealed)

BTW i'll be using 4k and co2......and will not be cooling the lights

:tiphat:
 
Ok, Hi everyone.
I read the thread and I didn't catch this info.
The room I'm building has one intake and one exhaust manifold for the air-cooled hoods. My plan is to hang the ballasts inside an insulated box within the room. It'll have a duct running to it and one running from it, just like the lamps. In other words, I'm planning to cool it with fan-blown air from outside, not the aircon.
Anyone see a problem with this, assuming sufficient airflow?
I had another question, but now I can't remember. KO Kush.
Thanks, SW
I remember the other question. How much impact will insulated ducting have on coolness? I have to run a lot of ducting.
 
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D

dubdi3mond

need a little help please, 13 x 13 x 8 room inside of room

r7 insulation between old wall and new wall and r13 between the studs of new wall

panda film, completely sealed room

There will be a 4x5 veg room with a 2 bulb 4' shop light for clones and 432w 8 bulb t-5 in this room as well as all the ballasts, co2 tank, a/c (window w/ ac box) and dehumid

2x 1000w, 2x 600w for flower side of room, the lights will NOT be air cooled, the hoods will be aaw's

on the hottest days of summer it reaches around 95-100 degrees and I would like to keep the temps around 77-82 give or take a few degrees

from my calculations I need either the 18k btu or 24k btu window unit but I dont want to be short cycling or get too large of an a/c, so what do you guys think?
 
Got a few questions on how I should cool my sealed room...

My room is in the lower level of a building (basement),the room was originally used as a cold storage room.the room is built into the side of a hill and gets no direct sunlight.

The room is 10' x 15' x 10',with an adjoining room appx about 10' x 5'

Do I need to go with a mini split system or could I use a portable unit or window unit vented into the adjoining room?(adjoining room is also sealed)

BTW i'll be using 4k and co2......and will not be cooling the lights

:tiphat:

I think a split is always preferable.
 
D

dunkybones

A fundamental premise I can't quite figure out is if these calculations are meant to exchange the heat of the bulbs whether or not they ultimately have air cooled hoods.

My system as it stands now is venting 3K of lights from an outside room through the lights and up a chimney. But all this reallly does from an Hvac perspective, is move 600 cfm through my house on a constant basis, like leaving a giant window open, so now my basement gets hot in the summer whereas it used to stay cool.

Should the ac be sized to exchange the heat of the lights being vented back into the outside room, instead of up the chimney?
 

gus738

Member
questions on how I should cool my sealed rooms

i did my 4x5x8 veg room and a 7x5x8 flower room. inside a garage
gets no direct sunlight. the only window 3x6 is facing neighbors house.

should i get with a mini split system or could I use a portable unit or window unit or a bigger unit?

and should i get a total of 2 units or 1 unit? im more concern as far as electricity per month rather then initial cost of product

will be using (4) 1k hps for flower and (2) 1k's mh for veg (atleast 1k)

will be using air cooled hoods magnum 6" (should duct /exhaust with ac or just a fan pushing for just the lights?

the total room size inside garage is 11ft x 12x8 single stud 2x4 but only using 4x5x8 and 7x5x8 the rest wall/room is for me

used homedepot insulation and drywall pasting on edges and then drywall sheet 5/ 8 .

should i vent or get dehumidifier and ac?
 
this threaD is great!

this threaD is great!

I just want to say thanks to IC mag for all the info over the last few years!!!:dance013:

I just picked up a 20 seer 12,000k btu mini split system at the SD hydro expo. I'm planning on running this unit to cool 4k of light that will be air cooled with 200+ cfm per light.

The ballasts will be in another room with a window unit on a flip flop system with an a-joining room thats gonna be cooled with a 24k window shaker

I fear is (not that big of a deal) that the 12k mini split wont do the job all the way, and I may have to put in a window unit to help it out.

Any feed back?

The ambient temps are hi 90's durring the summer months.

Thanks IC MAG!!!!!
 

Ganglere

Member
Great info here :)

Is it neccessary to work with the btu's? I live in a country close to the north pole where nobody has ever dreamt about installing COOLING in their house... Dedicated AC is actually hard to find, so I'll have to use a heat pump instead. But these are only rated with watts, not Btu... It took some wind to get here, but my point is, can I do the same math with watts? Turning it into Btu seems rather foolish to me, but what do I know? :)

Peace and Grow, G
 
R

RedRain

normally you can cool 3000w with 1 ton of cooling,,,co2 burners count as 1000w if they are not water cooled. so a 5 ton will cool 15X 1000w bulbs or 14 X 1000w and 1X co2 burner.

Small portable a/cs, ductless splits or mini splits lack the CFMs that a true air to air split will have. For this reason you will always have to oversize when cooling in a sealed room with ether one of them. When you have a real air to air split system with a full sized condensor and air handler my 3000w per ton will work. BTW 12000 btu= 1 ton


I just want to say thanks to IC mag for all the info over the last few years!!!:dance013:

I just picked up a 20 seer 12,000k btu mini split system at the SD hydro expo. I'm planning on running this unit to cool 4k of light that will be air cooled with 200+ cfm per light.

The ballasts will be in another room with a window unit on a flip flop system with an a-joining room thats gonna be cooled with a 24k window shaker

I fear is (not that big of a deal) that the 12k mini split wont do the job all the way, and I may have to put in a window unit to help it out.

Any feed back?

The ambient temps are hi 90's durring the summer months.

Thanks IC MAG!!!!!

does that mini split have sealed threaded quick connect lineset or is it flared ends? If its flared you will need a vacuum pump, and refrigeration manifold to vacuum down to under 500 microns before you start the system.


Check out hoosierdaddys thread on building ac boxes. That thread is golden.
As for mini-splits, I have a 9k btu unit that has heat mode and uses inverter technology and was delivered to my door complete (and I mean complete-pre charged with r410, line set with flared connections so all you need are wrenches instead of soldering, power lines, etc) for $1100.
I can tell you from experience that mini splits are ultra efficient, especially the ones with inverter.
Hope this helps...Evl

if the linesets are flared you still have to vac down the lines. The lines are small enough that you do not need to add refirgerant if your lines are anywhere from 1ft to 60 ft. Unless you have a sealed threaded lines, you will still need to pull your lines down to 500 microns at least before u start your system. Are your line sets open? When you look into the flare nut can you see the inside of the line?? The unit will be precharged with R410, but normally the lines are not. They should be under vacuum.

The inverter just lets you run the ac during the winter and more efficently. Get a heatpump so u can run it in AC mode in even colder weather. The inverter slows down the speed of the condsor fan relative to the outdoor temp and the load on the machine. When its cold, if the condensor fan is running non stop, your coils will freeze up. The unit slows down the fan allowing the coils to heat up.

If you are serious you need to get a real ac system with an airhandler. When you have a proper coil and outdoor unit, you must have 400cfms per ton blowing across the coil. You will get much more airflow and cooling capacity with a proper unit. These mini splits, window shakers, and portable a/cs dont even begin to compare to a 20 seer or 13 seer air to air split system. You just cant get the power, reliability, or efficency of a true ac sytem.
 

61-50-7

Member
Small portable a/cs, ductless splits or mini splits lack the CFMs that a true air to air split will have. For this reason you will always have to oversize when cooling in a sealed room with ether one of them. When you have a real air to air split system with a full sized condensor and air handler my 3000w per ton will work. BTW 12000 btu= 1 ton

If you are serious you need to get a real ac system with an airhandler. When you have a proper coil and outdoor unit, you must have 400cfms per ton blowing across the coil. You will get much more airflow and cooling capacity with a proper unit. These mini splits, window shakers, and portable a/cs dont even begin to compare to a 20 seer or 13 seer air to air split system. You just cant get the power, reliability, or efficency of a true ac sytem.

I'm confused as to the difference between regular central air and a mini-split.

Couldn't a regular air handler be attached to a mini-split or the mini-split handler modified with a fan to distribute cooling more efficiently?

I'm only trying to re-invent the wheel because installing a mini-split can be done in private without the help of an hvac pro.
 
R

RedRain

I'm confused as to the difference between regular central air and a mini-split.

Couldn't a regular air handler be attached to a mini-split or the mini-split handler modified with a fan to distribute cooling more efficiently?

I'm only trying to re-invent the wheel because installing a mini-split can be done in private without the help of an hvac pro.

a true air to air split, consists of a full sized condensing unit, and a "A" frame evap coil inside an air handler. You can install a true air to air split just as easy as a ductless split or mini split, as long as you get quick connect sealed fittings on the indoor, outdoor unit and linesets.

the compressor of a mini split will not have the capacity to be paired with a full sized air handler.

mini splits are compact, but over priced and not that efficient, not to mention terribly picky.
 

41hope

Member
Seeking advice Btu's

Seeking advice Btu's

Planning on a 4k grow in a 10x10x8 upstairs room that has an ambient temp of 73 located in the desert. I will have 4 air cooled lights with 2 8 inch fans & ducting. Ballast out side room. Air cooled lights will get air from house air condition duct and vent thru other duct in room that I believe sucks air out. I keep house air conditioner at about 72 degrees. Need to add window ac that will have back end thru wall into other bedroom. Currently have 7800 btu what are my chances that this window ac will keep room in high 70's low 80's? Also using Co2 burner & dehumidifier? When air cooling light should I run fans at full speed? If you believe I will need bigger AC please give me recommendations on which mode to run it on, brand, size and best place to purchase.
I truly appreciate your assistance!
 
R

RedRain

too hard to tell, too many variables

length of ducting, bends, power of fans,,,etc etc

i would say get a 12,000 BTU and call it a day. if you are air cooling your room and its working, your AC will not have to work that hard, and will not be using as much power vs just having the AC running. my 2 cents.

all portables suck,,try and get one that is auto restart and one that has a temp probe.
 

ivanic

Member
working out ac, does this look right to use

Ballast and fans are not in the room
very well insulated
ambient temp is around 65

So my room is 13x13x6 (LXWXH) 7840 BTU
5600 Lighting not air cooled 22400 BTU

30240 BTU?

how much BTU would i need to calculate for a hydrogen pro co2 burner?
 

greenduck

Member
hey, are you saying that if i get the ac btu's right, and the ac should be on all the time when the lights are on...AND, i wouldnt need a dehumid in the room? the co2 unit only comes on from time to time....do you know how to calculate that into the equation? thanks! much help here for sure.
 

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