Indoor cabinets - what is more frequent: cooling or heating?

OG is worldwide community so I’d like to ask which problem is more common among our members. Cooling or heating?

POLL: Most of the time I need to …

  • I need to COOL my cabinet
  • I need to HEAT my cabinet

0 voters

Heating problem

Where I live we’ve got pretty much both problems… Most of the year (3/4) conditions are very cold and we need to heat to avoid damaging plants by freezing or stuck growth. Ideal is to switch night and day so that lamps heat the room during (outside) cold night. During lights off there is no such difference in temperature between outside and target inside temp so grower can save on heating.

For heating usually electric heaters are used only during period when lights are off. Another solution is to suck in air from living areas which is pre-heated. When lights are on it is also preferable to reuse the air and vent it into the living area. Because of smell this is only possible when using separate air circuit for lamp.

As pretty much ideal and universal solution is heat recovery ventilation (HRV) which can supply fresh air exchange. It can bring dried air into the room while not losing much heat energy. It also helps to reduce hummidity indoors and offer better climate control. This is in my eyes ultimate solution for saving electricity costs.

Cooling problem

In general during 1/4 of the year (June, July and August) there is predominantly need for cooling in my area. Again partly this problem is solved by switching day and night and having lights turned on during (colder) night. Due to high purchase costs growers try to avoid Air Condition systems and rather build over-size ventilation system (which is regulated by choking it up during cold months).

Those who take into growroom pre-heated air from living areas are hit with in summer big with this problem. Solutions include having separate air circuit for cooling the lights (using cooltubes and other air-cooled hoods) and another for cooling grow area. This way heated air from lamps is extracted quickly out of the room.

What is your take on these problems?


Any time I’ve ever used a cabnet to grow in the biggest issue was the heat inside vs the stealth of the fans.


Living in the desert, heating is not really needed. We really only have a few months of cold (December, January, Febuary). I run my lights at night not only because it’s much cooler, but also because I work and have a kid. I rarely get to my grow before 9 PM.

My workshop is only 10’x10’, so a small window A.C. keeps the room around 70°F. I have it on a temperature controller. Each of my cabs has its own fan and carbon filter also on a custom temperature controller set to 25°C. The temp controllers in my cabs will keep running the fan when at or below 25°C. The fan runs on a speed controller I can adjust for cooler weather. This keeps negative pressure in the cab and prevents smell from leaking out. When the temperature exceeds 25°C the fan is run at full power.

I only run about 700-watts total for all of my cabs. I try to balance out the load throughout the day. In fact, now that it’s getting cooler, I need to block off my central heat for that room. The heater and A.C. were battling it out the other morning. The heater wins! :laughing:


The humidity for me, to keep it below my red zone ^^


That’s a whole other subject for me. Usually low humidity in grow room (20%-30%).


I have to cool and heat… And deal with high humidity in the winter. This summer I used an oversized exhaust and lights off during the hottest part of the day. In winter I’m running a dehumidifier and an oil filled radiator and have turned the exhaust all the way down.

It works OK, but I feel like I’m wasting a lot of electricity. I’m thinking about switching from LED to an air cooled HID in the veg room and exhausting the dry air into the flower room.

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Just putting mine together and finishing it, and my guess is going to be the heat. Mostly because of climate and location of the box and the light i’m going to use it it for now. When I upgrade to LED strips the heating shouldn’t be half as much of a problem.

I’m only guessing since I haven’t even dry ran the box/cabinet.

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My grow tent is in my basement it’s alot cooler down there I’m trying to get the temperature within range before putting my plants in… As it sits with nothing running the temperature is around 13C inside the tent,.with a oscillating fan and LED light running it reaches around 18C and I’m thinking when the exhaust fan is running it’s gonna be back around 13C so i need to heat my tent, how do people do this? I’m thinking a space heater but looking for every option before i make a choice…

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A space heater takes more power than most lights, just get more lights lol. Seriously though the easiest way is usually to bring air into your grow from somewhere warm by running a flex duct or something like that.


That was my initial thought but that doesn’t do any good for lights out… And bringing outside air has crossed my mind as well only issue is the whole basement is around 13-14C so I’d have to pull it from the main level and i really don’t wanna start cutting holes in my house… I’ve done a search and i can see some people use space heaters but there isn’t much said about it… who all uses a heater to heat their tent and what are you all using ceramic , oil filled? Just looking for info and ideas, i see alot of heater saying to plug directly into the wall this is another issue for me… I have everything almost ready even some plants ready to go in but fighting with temps is holding me back, i came close many times to taking it all down and selling all the equipment I’ve bought, yay anxiety! Also a guy i work with says his temps go down to 5C during lights out and he says its no issue but it seems he is always fighting something whether it be mold or powdery mildew so that has me thinking I’d prefer to get my temps in a good range, a heater with thermostat seems like it may be the easiest way to get the temps dialed in. Does anyone have anything to point me in the right direction?

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Well if you did get another light you’d run them on 12/12 in alternating cycles so one is always on making heat, or run one 24/7 as a veg light or for autos. To take air from the house you might be able to tap into the cold air return which is usually in the basement.

Besides those and a space heater there real aren’t any other options that I can think of. Getting cold at night isn’t that bad, but I do think it encourages powdery mildew.

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Only problem with a space heater i have no plug close enough to eliminate the need for a extension cord and i read not to use a extension cord with a space heater.

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It’s not the best practice,but if the cord is rated for the same amperage as the breaker and not in water or anything (duh) then it should be ok. Keep in mind space heaters are usually 1200 watts or more so they usually need a dedicated circuit (breaker).

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That would be my plan it would have it’s own plug … i may have come up with a idea i will know when i get home after work… i will update when i know… involves warm air from my upstairs level

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Sounds intriguing, I love seeing what stoners can come up with lol

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Well this is what I’ve come up with

My finger pointing to a vent in the floor about 4 feet from my tent. Tent is just to the left of my finger.

I stuck a cedar shim up along side it to make sure it comes where i thought…

Which it did… My linen/pet food closet which has a heating vent right in front of it…

It’s staying at around 20.5 C so i am gonna run some ducting up the hole with a booster fan and suck in the warm air from the closet into the tent…
Now that brings me to this… i can’t decide between these 2 fans.

1 is abit more cfm but the 100 cfm would work to cause my exhaust fan would help when its pulling…

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Nice solution there. I’d go with the vivo for an extra few bucks it will be much more powerful.

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They’re both vivosun, you must mean the bottom one on the pic? I just don’t know if i need that much cause my exhaust sucking should also help with intake, i don’t want to much fan i am worried it may cool the warm air too much? Any input on that?

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Yes I meant the bottom one. Sometimes those come with dimmers to slow them down. You could just let your exhaust passively suck the intake air too.

I may start out letting the exhaust pull and see what i get for temps after they stabilize… may not need a booster