Grow Room A/C

[CannabisJohn]

hey guys

I've been looking to get two units of mini splits and wanted to know what kind of brand should I be looking at so I know which one to avoid like the plague. I've looked on thermospace and wanted to know if there are other places online or a physical store in North Cali that sells them at competitive prices.

so if i need roughly 48k btu should i get a single 4 ton unit or get 2 two ton units incase one fails and for even cooling since there are two handlers

Get 2 -2 ton units. I prefer Mitsubishi.

 

[evu80]

Get 2 -2 ton units. I prefer Mitsubishi.

if I get Mitsubishi units, I notice I will be 4000 btu short of what I need since they dont make 24k btu units but rather 22k btu. Or are they just as strong despite being a full two tons units

 

[witness0]

Hey Cannabis John. i was wondering about using an environmental controller like the iponic 600 or sentinel chhc4 with my 24k shinco mini split. not sure if you can connect the thermostat from the ac to one of these controllers.

 

[CannabisJohn]

Hey Cannabis John. i was wondering about using an environmental controller like the iponic 600 or sentinel chhc4 with my 24k shinco mini split. not sure if you can connect the thermostat from the ac to one of these controllers.

Never tried. Don't see a reason to try. Also don't think it will work.

 

[CannabisJohn]

if I get Mitsubishi units, I notice I will be 4000 btu short of what I need since they dont make 24k btu units but rather 22k btu. Or are they just as strong despite being a full two tons units

Should be fine. If you are worried go bigger as long as you get inverter style mini splits.

 

[jimbobthe3rd]

Dear John,

I'll be running 21-1k hps in magnum xxxl 8" air cooled hoods, three rows of seven. The room size is 50' x 30'. Very very well insulted built freestanding drywall room inside an insulted shed also. I'll have a max can fan 20" for exhaust that is rated near 4800cfm, and same for an evaporative air cooling system for intake. I'll also have a 24k btu window unit in the room for supplemental heating/cooling. I live in a moderate climate. I really want to over-do my air cooling of the hoods, as to minimize how much cooling i'll need for the actual room. Do you think i should use 7x 1000cfm fans for the magnum hoods in each row of 3, or go the other way with 3x 2500-3000cfm fans for each row of 7 hoods?

I'll have a large evaporative system bringing air in, and the 24k btu window unit. If i over-do my air cooling of the hoods, should i be able to maintain nice temperatures in my room?

 

[CannabisJohn]

Dear John,

I'll be running 21-1k hps in magnum xxxl 8" air cooled hoods, three rows of seven. The room size is 50' x 30'. Very very well insulted built freestanding drywall room inside an insulted shed also. I'll have a max can fan 20" for exhaust that is rated near 4800cfm, and same for an evaporative air cooling system for intake. I'll also have a 24k btu window unit in the room for supplemental heating/cooling. I live in a moderate climate. I really want to over-do my air cooling of the hoods, as to minimize how much cooling i'll need for the actual room. Do you think i should use 7x 1000cfm fans for the magnum hoods in each row of 3, or go the other way with 3x 2500-3000cfm fans for each row of 7 hoods?

I'll have a large evaporative system bringing air in, and the 24k btu window unit. If i over-do my air cooling of the hoods, should i be able to maintain nice temperatures in my room?

I would cool each row with a fan (7 fans). I am not sure you have enough cooling. My suggestion is to set up the room. Turn on everything w/o plants and do some testing. Make sure you do it for 6-8 hrs and keep a close eye on temps under lights. Normally I would want 80-90k of just a/c for your setup.

 

[jimbobthe3rd]

Thanks for your quick reply John, Ok, would i be able to cool each row with 7 fans, and then duct all the 8" fans into a large 20" duct running down the side of my room to the outside? I would love to run two very large ducts down both sides of my room so i can intake & exhaust all the hoods fans from those ducts so i need only two 20" holes for intake/exhaust for air cooling my hoods, instead of 14 8" holes if you catch the drift?

Also, have you heard anything about the max can fan 20 inchers? It's almost 1500 for the one fan, but its rated at 4600-4800cfm & is quiet due to low engine RPMs (1500-1700 rpms i think.) So i was gonna buy two of these, one for intake & one for exhaust.

My other route would be to buy four 14" max can fans that are rated 1700cfm & then maybe get 50k btus worth of cooling instead of just 24k.

(On a side note, i have a 24k btu mini split cooling the area in the shed, that is outside of my room for where the ballasts & back of my window unit A/Cs will be etc.)

Thanks for your help again, i'm just trying to figure out the most cost effective & efficient cooling system without using a bunch of mini-splits, and least amount of holes lol.

 

[CannabisJohn]

Thanks for your quick reply John, Ok, would i be able to cool each row with 7 fans, and then duct all the 8" fans into a large 20" duct running down the side of my room to the outside? I would love to run two very large ducts down both sides of my room so i can intake & exhaust all the hoods fans from those ducts so i need only two 20" holes for intake/exhaust for air cooling my hoods, instead of 14 8" holes if you catch the drift?

Also, have you heard anything about the max can fan 20 inchers? It's almost 1500 for the one fan, but its rated at 4600-4800cfm & is quiet due to low engine RPMs (1500-1700 rpms i think.) So i was gonna buy two of these, one for intake & one for exhaust.

My other route would be to buy four 14" max can fans that are rated 1700cfm & then maybe get 50k btus worth of cooling instead of just 24k.

(On a side note, i have a 24k btu mini split cooling the area in the shed, that is outside of my room for where the ballasts & back of my window unit A/Cs will be etc.)

Thanks for your help again, i'm just trying to figure out the most cost effective & efficient cooling system without using a bunch of mini-splits, and least amount of holes lol.

A single 20 inch hole won't handle 4600-4800 cfm. I wouldn't do more than 2000-2200 cfm down a single 20 inch duct.

 

[jimbobthe3rd]

Ah i see, i just got this from a HVAC website, it's estimates on the cfm ducting can hold.

4" Duct 40 cfm
5" duct 60 cfm
6" duct 100 cfm
7" duct 150 cfm
8" duct 200 cfm
9" duct 300 cfm
10" duct 400 cfm
12" duct 600 cfm
14" duct 900 cfm
16" duct 1,400 cfm
18" duct 1,800 cfm
20" duct 2,300 cfm.

Currently i'm running some 1700cfm rated 12" fans into 12" ducting, yet it says it can only hold 600cfm? I guess this just leads to an increase in pressure and lower efficiency of the fan?

So what's the point in having a 20" max can fan thats rated at 4800cfm, would you just use an up-sizing reducer and use like 30" ducting on the 20" fan? In most cases that i've seen, all the fans are cfm rated much much higher than the amount of cfm the same size ducting can hold, what is the point of this :s?

 

[CannabisJohn]

Ah i see, i just got this from a HVAC website, it's estimates on the cfm ducting can hold.

4" Duct 40 cfm
5" duct 60 cfm
6" duct 100 cfm
7" duct 150 cfm
8" duct 200 cfm
9" duct 300 cfm
10" duct 400 cfm
12" duct 600 cfm
14" duct 900 cfm
16" duct 1,400 cfm
18" duct 1,800 cfm
20" duct 2,300 cfm.

Currently i'm running some 1700cfm rated 12" fans into 12" ducting, yet it says it can only hold 600cfm? I guess this just leads to an increase in pressure and lower efficiency of the fan?

So what's the point in having a 20" max can fan thats rated at 4800cfm, would you just use an up-sizing reducer and use like 30" ducting on the 20" fan? In most cases that i've seen, all the fans are cfm rated much much higher than the amount of cfm the same size ducting can hold, what is the point of this :s?

It could be running actually a lot lower than it's rating depending on how much duct is attached. See this brochure from Can Fan for their Max Fan line of fans. A 8 inch fan can do from 100-667 cfm depending on how much backpressure (length of duct attached) is on fan. They also have a max pressure. If it reaches that pressure it will be moving no air.

 

[evu80]

hey John what do you think of this unit. Theyre 2.5 tons units cooling only which will save me a few hundred bucks. I dont see the need for heating. Are they any good??

http://air-conditioner-system.com/productdetails.aspx?ProductID=1136&categoryID=134

 

[CannabisJohn]

hey John what do you think of this unit. Theyre 2.5 tons units cooling only which will save me a few hundred bucks. I dont see the need for heating. Are they any good??

http://air-conditioner-system.com/productdetails.aspx?ProductID=1136&categoryID=134

Mitsubishi is one of the best.

 

[evu80]

sorry to bother you again John, but those mini splits came in above what Im able to pay atm.

Now i'm looking at central air systems to save quite a bit of money. Can you tell me whats the difference between central air, horizontal system and a two stage system. Which one should I be looking at to serve our needs. thanks again

 

[joehank]

I am about to upgrade my home service to 200amp, and then run a 100amp subpanel closer to my grow area which is about 15 feet away. Dan from Dxhydro is building me a loadcenter for 10K at 240v plus 10 120v outlets. He recommends a 70 amp breaker to connect it, which leaves me with 30 amps. I also would like to install a 4 or 5 ton split AC unit. My question's are, what voltage do they run on, and will the remaining 30a in my subpanel be enough to handle it? I know your supposed to not max it out but I don't know how close I'm coming.

 

[ttystikk]

Ah i see, i just got this from a HVAC website, it's estimates on the cfm ducting can hold.

4" Duct 40 cfm
5" duct 60 cfm
6" duct 100 cfm
7" duct 150 cfm
8" duct 200 cfm
9" duct 300 cfm
10" duct 400 cfm
12" duct 600 cfm
14" duct 900 cfm
16" duct 1,400 cfm
18" duct 1,800 cfm
20" duct 2,300 cfm.

Currently i'm running some 1700cfm rated 12" fans into 12" ducting, yet it says it can only hold 600cfm? I guess this just leads to an increase in pressure and lower efficiency of the fan?

So what's the point in having a 20" max can fan thats rated at 4800cfm, would you just use an up-sizing reducer and use like 30" ducting on the 20" fan? In most cases that i've seen, all the fans are cfm rated much much higher than the amount of cfm the same size ducting can hold, what is the point of this :s?

Hey Jimbob, hope I'm not too late to help address your questions. First, no matter how hard you blast air through sealed hoods, you will not be getting all the heat. Radiant heat will be flowing out of these hoods and into your room- and it's a good thing, since much of it is what your plants need from the lights in the first place!

So the game then becomes how can you get all the heat you CAN remove with the least amount of effort? For your setup, I'd do 7 rows of 3 hoods each all 8" straight duct, with an 8" fan- the normal type, not a Maxfan, so you can run it on a speed controller- at the downstream end of each row. Each of these should blow into your 20" exhaust duct, which should be insulated. This air should then leave the building. You need to get air from outside the building as well and resist the urge to blow air through these ducts; it creates far more heat than its worth.

This gets rid of roughly 2/3 of the heat generated by the lights. Your AC should be up to handling the rest.

 

[fishwhistle]

I am about to upgrade my home service to 200amp, and then run a 100amp subpanel closer to my grow area which is about 15 feet away. Dan from Dxhydro is building me a loadcenter for 10K at 240v plus 10 120v outlets. He recommends a 70 amp breaker to connect it, which leaves me with 30 amps. I also would like to install a 4 or 5 ton split AC unit. My question's are, what voltage do they run on, and will the remaining 30a in my subpanel be enough to handle it? I know your supposed to not max it out but I don't know how close I'm coming.

2-2 ton minis will take around 40 amps themselves,lights are like 4.5 amps each so your at 85 with a/c and 10 lamps,not much of a safety factor and you still havent factored in misc fans,dehuey,pumps or anything else.On a 100 amp circuit id feel comfortable using 80% or 80 amps leaving a 20% safety factor.Solutions?two rooms on a flip with seperate mini splits for each room so only one set of lights is on at a time and cooling is minimal in the lights out room,also consider only 4-1ks in each room to save another 9 amps.30 amps is not enough to cool 10k in lights imo but the bigger problem is no safety factor,pulling 100 amps out of a 100 amp breaker is akin to only driving your car at wide open throttle/max rpms constantly.Id reconsider that loadcenter or buying any equipment until you figure out how much power you have ''usable''.

 

[joehank]

I'm pretty sure the 70amp was already factoring in a little extra for the loadcenter. Does the AC run on 120 or 240 ? ( not a mini split, a home central air type unit?)

 

[CannabisJohn]

I am about to upgrade my home service to 200amp, and then run a 100amp subpanel closer to my grow area which is about 15 feet away. Dan from Dxhydro is building me a loadcenter for 10K at 240v plus 10 120v outlets. He recommends a 70 amp breaker to connect it, which leaves me with 30 amps. I also would like to install a 4 or 5 ton split AC unit. My question's are, what voltage do they run on, and will the remaining 30a in my subpanel be enough to handle it? I know your supposed to not max it out but I don't know how close I'm coming.

A/C runs on 240v and 30 amp will not be enough for a 4 or 5 ton. Need 40 amp.

 

[joehank]

ok thanks. I will be going to NG on my dryer and oven to free up space in my panel, plus another 40 amps that I ran for outlets in the grow room before. So that should free up enough to put the AC on the main panel, and still have my subpanel for the rebuild of the growroom.