Grow Room A/C

[CannabisJohn]

I'm up grading my room from 6 1k air cooled hoods to 6 1k Gavitas. I'm not running any type of cooling at the moment but will obviously need something. The room size 11x11 with standard ceilings.
I have looked and spoked to the guys at Excel air and they said a 2ton because they are more efficient than a mini split.
I think I need a 3 ton at least and being the room is small distributing the cool air should be easy with some fans?
I just want to do it right the first time and if doing it right cost a bit up front that is ok as well. Buying twice always cost more than doing it right the first time.

Excel Air straight up lied to you. A Mr Slim is more efficiency than their POS. I would do a 3 ton.

 

[soaringfast]

Thanks CJ....You are truly invaluable to us cultivators.
I will be getting a Mr Slim 3 ton on your credibility.

 

[greendarknight]

If you don't need to heat ur grow you don't need additional heat. Just make sure the outside unit can provide cooling to ur lowest outside air temp.
Your existing units can't provide proper cooling when the temps get too low. There are units that will do that. Sometimes you need to add additional manufacturer provided components installed to accomplish this. I recommend Mitshubushi mini splits. I believe the P series units can run to 0F outside out of the box. Your a/c tech should be able to help you further with your selection. PM me if I can help you further.

We do need to warm the building but not inside the room.

Thanks man, I really appreciate your reply. I am going to look into the P series. Looking around to find a trustworthy HVAC guy.

 

[indogro]

CannabisJohn, your insight would be greatly appreciated here.

. Flower room is 25ft long x 8 ft wide x 7ft tall. 200 sq ft, and 1200 cu. ft. In a basement, with 3 walls insulated underground, and one wall of plastic to the basement.

. 6 - 1k lights, in a long row. currently air cooled, pulling air from other room in basement (giving me some negative pressure for smell) going through the lights and vented into house duct system. currently helping warm the house.

. 4 Burner C02

. 60 pint dehuey for night time.

. 10in Max fan push air on one end through lights, sucking through filter, and 8in Max fan on other end right before it goes into house duct.

. air temp going through lights is about 78-80 degrees, because this air is coming from veg room. yeah, i know.

. when it's all cranked up at full blast, my room is hitting 90 degrees.

it seems this is a poor attempt at cooling the room. It's nice having the warm air heat the house, but come spring and summer, I'll probably be hating it.

I think I'd like to kill the air cooling, keep the room sealed, and add a mini spit.

for 6k in those dimensions, what is a proper mini split setup I should install? I want total control. And if I am sealing the room with no air cooling, I might have to go gavita here pretty soon...

please help!!

cheers.

 

[CannabisJohn]

CannabisJohn, your insight would be greatly appreciated here.

. Flower room is 25ft long x 8 ft wide x 7ft tall. 200 sq ft, and 1200 cu. ft. In a basement, with 3 walls insulated underground, and one wall of plastic to the basement.

. 6 - 1k lights, in a long row. currently air cooled, pulling air from other room in basement (giving me some negative pressure for smell) going through the lights and vented into house duct system. currently helping warm the house.

. 4 Burner C02

. 60 pint dehuey for night time.

. 10in Max fan push air on one end through lights, sucking through filter, and 8in Max fan on other end right before it goes into house duct.

. air temp going through lights is about 78-80 degrees, because this air is coming from veg room. yeah, i know.

. when it's all cranked up at full blast, my room is hitting 90 degrees.

it seems this is a poor attempt at cooling the room. It's nice having the warm air heat the house, but come spring and summer, I'll probably be hating it.

I think I'd like to kill the air cooling, keep the room sealed, and add a mini spit.

for 6k in those dimensions, what is a proper mini split setup I should install? I want total control. And if I am sealing the room with no air cooling, I might have to go gavita here pretty soon...

please help!!

cheers.

I would use a 3 ton which will take care of 6k of unvented lights.

 

[indogro]

I just got a quote from a local ac company to install a Mitsubishi 2.5 ton M series mini split in my room.

They quoted me $3800 with install. this includes indoor and outdoor unit, pad, all the wiring, etc. No thermostat, and I'll install the breaker and run the electrical too it for him to connect.

Is this price a bit high?

 

[hogan400]

Hey CJ,
Im building a new location and have decided to do something larger. I have 2 rooms. Both are 30'X60' with 25' ceilings.
Insulated well and standard commercial units with the big roll up doors. I will Run 24 lights in each, they will be sealed.
I have a good hvac guy and we've discussed the project. I have decided on the "Goodman Daikin 10-12 ton unit. 1 per room.
Are these quality units? These compressors will be outside, with the air handler inside. He says
'do 2 plenums to filter and duct, and a few circular overhead vents with a single intake down low. What do you think?
I was going to order them from Ingrams off ebay since there's no warranty on shit now days anyway and the obvious 200 pint commercial dehueys per room..

Am I on the right track Again?

 

[CannabisJohn]

Hey CJ,
Im building a new location and have decided to do something larger. I have 2 rooms. Both are 30'X60' with 25' ceilings.
Insulated well and standard commercial units with the big roll up doors. I will Run 24 lights in each, they will be sealed.
I have a good hvac guy and we've discussed the project. I have decided on the "Goodman Daikin 10-12 ton unit. 1 per room.
Are these quality units? These compressors will be outside, with the air handler inside. He says
'do 2 plenums to filter and duct, and a few circular overhead vents with a single intake down low. What do you think?
I was going to order them from Ingrams off ebay since there's no warranty on shit now days anyway and the obvious 200 pint commercial dehueys per room..

Am I on the right track Again?

I am not a big fan of Goodman. I think your ceilings are way too high. There is warranty on stuff. Unusually the compressors are 5-10 years. Look at York or Trane. Will be more expensive. Also make sure u get low ambient kits installed if your night temps get below manufacturers requirements ( usually around 54-60F).

 

[CannabisJohn]

I just got a quote from a local ac company to install a Mitsubishi 2.5 ton M series mini split in my room.

They quoted me $3800 with install. this includes indoor and outdoor unit, pad, all the wiring, etc. No thermostat, and I'll install the breaker and run the electrical too it for him to connect.

Is this price a bit high?

Get a 3 ton. Price is reasonable. Where are u located?

 

[indogro]

Get a 3 ton. Price is reasonable. Where are u located?

I'm in Portland, OR.

AC guy said he has set up many rooms, and told me a 3ton was overkill. He suggested a 2 ton, and we met in the middle on a 2.5 ton.

Do you strongly suggest a 3 ton? I want to do this correctly and not undercool the room.

again, 6k in 200 sq ft, 1200 cu ft. 8ft x 25ft x 7ft tall. C02 burner. I will not air cool, and remove all the glass. Sealed room.

all in underground basement which is well insulated.

Thank you!

 

[CannabisJohn]

I'm in Portland, OR.

AC guy said he has set up many rooms, and told me a 3ton was overkill. He suggested a 2 ton, and we met in the middle on a 2.5 ton.

Do you strongly suggest a 3 ton? I want to do this correctly and not undercool the room.

again, 6k in 200 sq ft, 1200 cu ft. 8ft x 25ft x 7ft tall. C02 burner. I will not air cool, and remove all the glass. Sealed room.

all in underground basement which is well insulated.

Thank you!

He is most likely right cause he knows the local area better but Mitshubushi M series are inverter so extra 1/2 ton should be no problem.

 

[Papa]

hey John. 'hope all is going well with you.
when exhausting a sealed room with a 6" inline, 24v dampers, is there a preference to pulling the air outta the room with a passive intake . . . or pushing the air into the room with a passive exhaust duct?
thanks.

 

[CannabisJohn]

hey John. 'hope all is going well with you.
when exhausting a sealed room with a 6" inline, 24v dampers, is there a preference to pulling the air outta the room with a passive intake . . . or pushing the air into the room with a passive exhaust duct?
thanks.

No preference. I am doing well. Headed to Cannabis Cup tomorrow with the wife. Never been to one. Hope all is well with you and yours also.

 

[Papa]

thanks, bro.

 

[DoomGada]

6 12 x 20 rooms with 8000k per room, rooms are built inside another structure that is super insulated. I would prefer to use unvented hoods but thinking of going with vented to keep AC costs down. The outer building is 60 x 100 with 20 ft cielings with two huge exhaust fans at opposite ends and a 10 tone AC unit that hardly runs because of the 9 inches of foam insulation throughout. (warm in winter, cool in summer). Im curious how some of you might set up the ventilation and AC

 

[CannabisJohn]

6 12 x 20 rooms with 8000k per room, rooms are built inside another structure that is super insulated. I would prefer to use unvented hoods but thinking of going with vented to keep AC costs down. The outer building is 60 x 100 with 20 ft cielings with two huge exhaust fans at opposite ends and a 10 tone AC unit that hardly runs because of the 9 inches of foam insulation throughout. (warm in winter, cool in summer). Im curious how some of you might set up the ventilation and AC

IMO each room needs at least 3 tons. So you could run the rooms on flip flop. 3 on and 3 rooms off. This is if you vent the lights properly.

 

[DoomGada]

Today set a record for high temp here (83) for this date. It gets plenty hot here in summer, 100 plus. The outside air I was referring to was air from outside the growroom, so it could easily be air from inside your house, just not from inside the growroom. That's what I do, and it works tits... In fact, I don't recommend people use air from outdoors because the large temperature swings make mantaining stable conditions more difficult, plus the possibility of drawing nasties into your sealed growroom.

Let's take a worst case scenario, however, and you'll see this still saves cooling costs; let's say you bring 100 degree air in to cool your bulbs. Let's say that this air is kept separate (like it's supposed to be!) from all other air, including the growroom air. To do this properly, you'll want to use insulated ducting and perhaps hood blankets too, but unless you have some long runs it isn't required. You'll still come out ahead, I promise. If the temperature rise drawing that air through your hoods is 25 degrees, the air being pulled (never push air through hoods if you can help it!) out of the room is 125 degrees. Place the duct fan of your choice Downstream of the bulbs and as close to the exit as possible. For sure, insulate any ducting between the fan and the exit, it will be hot no matter what its temp was when it came in. The hot air then goes outside. You've still successfully gotten rid of most of the heat the bulbs are generating! The only thing left for the AC to cool is the radiant heat from the bulbs, which is what the plants are using to power their growth, and of course whatever else is in the room generating heat.

While this approach will not eliminate the need for active cooling, it will reduce the amount needed. As a bonus, the air used to cool the hoods should not pick up any smell on its trip, since it's supposed to be fully sealed off from the growroom air anyway, so there's no need for odor mitigation. It can be shut off when the lights are off, I suggest a 15 minute delay on startup and shutdown, so it allows the room to warm properly in the 'morning' and shed the residual heat at 'dusk'.

Just curios, lets say you had

IMO each room needs at least 3 tons. So you could run the rooms on flip flop. 3 on and 3 rooms off. This is if you vent the lights properly.

Rather than try to bore you with the different ways we thought of doing this, lets say we flip the rooms, how would you go about exchanging the air to utilize fewer ac units?( trying to get away with only three.) On the backside of the rooms there is a 10 x 70 room which is the back side of the building and leads to the outside, would you pull air from the outside and vent it into the big room and let the large room use its large vents to illiminate the air, or would you pull air in from the large room and vent it to the outside?

 

[DoomGada]

IMO each room needs at least 3 tons. So you could run the rooms on flip flop. 3 on and 3 rooms off. This is if you vent the lights properly.

another question is what about a multi-zone mini split system? What size do you recommend and how would you set it up? We are trying to keep the cost down because obviously this is a large project, what size fans would you use to exchange the air? Would you have one pulling air from each room? if yes What size? and would you use intake fans? what size?

 

[DoomGada]

IMO each room needs at least 3 tons. So you could run the rooms on flip flop. 3 on and 3 rooms off. This is if you vent the lights properly.

and what about dividing the 10 x 70 into six bladder rooms, with a multizone mini split in each and pulling passive air into each room. if we are flipping the rooms then on three rooms would be on at a time exchanging air with it's off counterpart.

 

[CannabisJohn]

Just curios, lets say you had

Rather than try to bore you with the different ways we thought of doing this, lets say we flip the rooms, how would you go about exchanging the air to utilize fewer ac units?( trying to get away with only three.) On the backside of the rooms there is a 10 x 70 room which is the back side of the building and leads to the outside, would you pull air from the outside and vent it into the big room and let the large room use its large vents to illiminate the air, or would you pull air in from the large room and vent it to the outside?

I would use outside air (from outside bldg back to outside bldg) to cool light hoods for saving a/c. Multizone mini splits only total 4 tons and are very expensive. Use the existing unit to run 3 tons of air or so to all six rooms with zoning controls. Have only 3 rooms with lights on at same time. This will work if rooms without lights on do not need a/c or very little. This way u will not have to add any more a/c to rooftop. Your could put a 3 zone 3 ton multi zone mini split for the flower rooms when lights are out. Use 2 of these to do all 6 rooms. That would be your simplest way IMO and adds two more a/c. Each room could have up to 4 tons when lights on and 1 ton when lights are out. Make sure tstats are programmed so lights out room can't use main a/c. Where are u located ?