Air Conditioner Units

[BII]

Why buy an AC when you have a full house of ideal climate-controlled air available? With temp. "steady 74-76 and around 44%-46% humidity," you have what most or many consider ideal for air conditioning - room temp. with humidity about 50%. As has been suggested, blow/suck house air through the tent. You can either exhaust the heated air to outside, out a window, or into the tent room (with good whole-house circulation, or will need a room window or portable AC).

I think in the worst case you could cool the room with a cheap used window air conditioner, and exhaust the heated tent air out the same window. That's what I do. In terms of controls, this can't compete with the fancy grow-targeted AC units, but thermostats in AC units and thermostat electrical outlets can do what is needed more than very well.

 

[Oldfartnoclue58]

Yeah, no basement here. I am getting my crawlspace encapsulated again, that should give me more consistency with temps and humidity in the house. Also, I've got central air so no window units. Tried a swamp cooler but that requires constant watching not counting the heat it puts off. I appreciate the ideas. This is why I joined here. You guys rock.
Thanks.

 

[Frankthetank]

Yeah, no basement here. I am getting my crawlspace encapsulated again, that should give me more consistency with temps and humidity in the house. Also, I've got central air so no window units. Tried a swamp cooler but that requires constant watching not counting the heat it puts off. I appreciate the ideas. This is why I joined here. You guys rock.
Thanks.

I use my central AC to keep temperatures in range in the tent…..bottom flaps need to be open, and your extraction fan high enough to create negative air pressure inside the tent….so you’re sucking cool air in through the bottom flaps, and hot air is being filtered and exhausted through your extraction fan…. Then just keep your house cool enough…. The AC will also dehumidify…

 

[Oldfartnoclue58]

Yeah I've got it set up with the bottom and one upper side hole are open, then I've got a 6" A/C Infinity mounted on the outside of the tent, ducting to the top hole to pull the hot air from. Then I have a 4" mounted on the other side pulling hot air out also. 2 6" circulating fans on the inside and then the Vivosun 200SE has a fan in the center of the lights. I have those set to a natural wind setting that does gusts, the outside fans are set on constant run based on temp. I usually set them to around 74 and 50% in the grow tent and 73 and 60% in the dry tent. If i set the temps any higher then about once or twice a day temps will rise over 80-85, don't know why. In the dry tent I need to get a controller for the humidifier so I can keep that about 55%-62% at all times. Any suggestions please let me know. The one in the dry tent is the A/c T3. Then I have the Vivosun 4.5L in the grow room just outside of the tent. I have a 4" Vivosun fan on the outside of the dry tent pulling heat from the top hole. Then I have 2 fans inside the dry tent blowing air around. The grow tent is a 2x4x6 and the dry is a 3x3x6. Any suggestions, improvements, changes, I am open minded to all .

 

[BII]

Regarding "I've got central air so no window units:" Using central whole-house AC to cool a continuously exhausting tent or tent room is surely inefficient (even presuming the exhaust fan is run on a thermostat, vs needlessly exhausting continuously). You're pulling/sucking pulling hot outside air into the other parts of the house and having to cool the whole house vs. just ventilating and cooling the room where the tent is.

Consider that adding a window AC in that room will be more efficient vs. cooling the whole house just to use a small portion of central AC'ed air to cool the tent. Similarly, I locally see a fair no. of homes with central AC running window units in bedrooms at night. And what do you do if you leave the house for a while when it's hot? You cool the whole house down to ~74˚F when no one is home just to cool the tent room?

Otherwise, 74˚F is on the cool side for our plants. I keep my tent (set exhaust fan thermostat switch) at 80˚F +/- 1˚. With adequate in-tent ventilation/fans, reaching 80-85˚F for a while each day is not going to affect the plants.

 

[Cannaficionado]

Along with what was said up above. I dont know if its feasible, but if I need a little boost of ac in my grow space, I block off some registers that are also supplied by the same main duct. In my basement its always a few degrees cooler but some days it does get hot and during heat waves I can close off my back room and bathroom and open the vent in the basement all the way. Takes a little longer to cool the upstairs but in you're situation it might not be that bad. Usually it knocks the temp down a few degrees past where my thermostat is.

 

[Oldfartnoclue58]

Cool, good to get confirmation on that. I'm so paranoid from my SiL's last disaster, that I just always worry about getting in the red zone on temps and humidity. This is my 1st time in taking charge of the grow, so I'm like the parent with a new baby, scared of everything, lol. Now that you mention it, my room was always the coolest in the house before the tent, so I'll check the registers and see what's open but not needed. Haven't done a check on what's open in awhile, so it's due.
Thanks .

 

[BII]

Closing central AC vents will help concentrate cooling where you want, but still is very wasteful/inefficient, indirect vs. running a much smaller capacity window unit in the same room where you need the cooling.

Also, the central AC blower might not like having a lot more resistance/back pressure with a good number of vents closed off. In the extreme, you could overheat the motor or cause it to break down earlier. With closed vents, you persumably need a more powerful motor vs. the current one surely designed for cruising along with nearly all vents being open (little back pressure) to cool the whole house.

 

[Oldfartnoclue58]

Thanks Bill, I appreciate the info & advice. Got a couple of weeks before I get started again, so it gives me some time to play around with some things.
Thanks .

 

[Delps8]

If your lung room is 74-76 and RH 50%, that's an excellent start but I think that getting the Terraformer (vs just a dehu) is really a question of how close you want to be to optimal.

"in the red zone on temps and humidity."-what are your "red zone" values?

"I usually set them to around 74 and 50% in the grow tent and 73 and 60% in the dry tent. If i set the temps any higher then about once or twice a day temps will rise over 80-85, don't know why. In the dry tent I need to get a controller for the humidifier so I can keep that about 55%-62% at all times. Any suggestions please let me know. The one in the dry tent is the A/c T3."

I set my temps based on the research of Mitch Westmoreland, now Dr. W, who is/was a student under Bruce Bugbee. In ambient CO2, up to 82° in veg and tops of flowers <=78° in flower. Until I get the AC Infinity dehumidifier ("available in Q4") I'll stick with the large dehu that I have in the lung room and let my Controller 69 Pro Plus run the AC Infinity Cloudforge to keep my VPD at optimal values.

I take that approach because in the four years that I've been growing, I have found that to be a good way to remove the "aw shits" and reduce the "oopsies".

You could probably use the same setup that I'm using and get temperature+ RH/VPD very close to optimal but the Terraformer would get you even closer and will probably let you run CO2.

NB—I'd also put $219 into a Spider Farmer G4500 or spend $300 for two Migro Aray 150's because all of the environmental tuning is no substitute for giving your plant good light. Cannabis crop yield and quality increase directly with PPFD and a 200 watt light in a 2' x 4' is a significant constraint.