Need Advice For Regulating Basement Grow Tent Climate

[farmer.b]

So I am doing my first grow and unfortunately I am flowering in the middle of summer and having issues controlling the climate. Specs:
-Week 3 of flower
-4x4x6 grow tent in the basement
-4 in. 200 cfm exhaust fan with scrubber venting to the outside world
-2 clip on fans and a small floor fan for air circulation
-4 in. 200 cfm fan for intake drawing air from basement room
-600w vero29 COBS
-Lights on starts at 9pm ends 9am to try to get cooler temps with lights on

So my basement temp sits around 78 Farenheit 55% hum. average so when lights are off there isn't much of a heat issue, but when lights are on I need to keep them dimmed pretty low in order to avoid high heat(getting into low-mid 80's).

I am thinking of getting my intake air from the outside and bringing it in so that during the night time (lights on for plants) it can bring in cool night time air and help with heat. However, I am worried that during the day outside temps will be in the high 80s and this will cause high heat during lights off.

I have looked into swamp coolers that could help cool the tent off but I am worried that they will increase humidity too much.

I am trying to avoid getting a portable AC since that means $$$ both for the unit and electric.

Does anyone have experience with basement grows and controlling the climate that can give me any tips here? Getting worried as I get later in flower without stable climate control. Also, dimming light down so low will probably not be good for harvest if I cant correct things.

 

[G gnome]

So I am doing my first grow and unfortunately I am flowering in the middle of summer and having issues controlling the climate. Specs:
-Week 3 of flower
-4x4x6 grow tent in the basement
-4 in. 200 cfm exhaust fan with scrubber venting to the outside world
-2 clip on fans and a small floor fan for air circulation
-4 in. 200 cfm fan for intake drawing air from basement room
-600w vero29 COBS
-Lights on starts at 9pm ends 9am to try to get cooler temps with lights on

So my basement temp sits around 78 Farenheit 55% hum. average so when lights are off there isn't much of a heat issue, but when lights are on I need to keep them dimmed pretty low in order to avoid high heat(getting into low-mid 80's).

I am thinking of getting my intake air from the outside and bringing it in so that during the night time (lights on for plants) it can bring in cool night time air and help with heat. However, I am worried that during the day outside temps will be in the high 80s and this will cause high heat during lights off.

I have looked into swamp coolers that could help cool the tent off but I am worried that they will increase humidity too much.

I am trying to avoid getting a portable AC since that means $$$ both for the unit and electric.

Does anyone have experience with basement grows and controlling the climate that can give me any tips here? Getting worried as I get later in flower without stable climate control. Also, dimming light down so low will probably not be good for harvest if I cant correct things.

Ur basement only gets down to 78 at night?

 

[farmer.b]

Ur basement only gets down to 78 at night?

Ya I think its because I have a couple Dehum's running 24/7 to try to keep humidity in check. Although without them it still only gets down to like 75.

 

[farmer.b]

I'm thinking of rigging up ducting from dehum to inside of grow tent and putting it on inkbird trigger but I am worried about temp increasing as I lower humidity. Although, thinking about it thios will hopefully lower basement temp since i am just dehumidifying the tent and not surrounding room

 

[crimsonecho]

Ya I think its because I have a couple Dehum's running 24/7 to try to keep humidity in check. Although without them it still only gets down to like 75.

Why not get an ac, you can stop using those dehumidifiers too. A split would be nice. I am doing a grow too in the middle of summer and day time temps are 30-34C outside, also i don’t have the option to vent outside as i am trying to keep a low profile, so all that heat from the light and equipments build up, it is worse than a basement grow. I pull air from my bedroom with a 10 meter aluminium air duct where there is a split unit and it runs 24 hrs at 23C, temps in the tent are 26.8 max. Humidity was 65-70 now 45.

 

[farmer.b]

Why not get an ac, you can stop using those dehumidifiers too. A split would be nice. I am doing a grow too in the middle of summer and day time temps are 30-34C outside, also i don’t have the option to vent outside as i am trying to keep a low profile, it is much like a basement grow. I pull air from my living room with a 10 meter aluminium air duct where there is a split unit and it runs 24 hrs at 23C, temps in the tent are 26.8 max. Humidity was 65-70 now 45.

I am considering an AC but it's my last option since gonna cost ~$300 just to buy it and then the electric it will use will be more money. Not to mention finding a way to exhaust hot air outside. I was considering putting a y duct connector to connect tent exhaust fan and A/C exhaust but I am not sure if when the A/C is off, the exhaust fan will push air down the other pathway into the A/C and what effects this would have. I also have no way to pull from an upstairs room into the tent.

 

[Dbear180]

Why are you worried mid 80s is a nice day for a plant lol

 

[farmer.b]

Why are you worried mid 80s is a nice day for a plant lol

I want to be able to turn my light output up to help yield. Right now im at like 20% output to keep heat somewhat in check. If I went 100% light temp would hit 90 and they wont be happy

 

[Dbear180]

I want to be able to turn my light output up to help yield. Right now im at like 20% output to keep heat somewhat in check. If I went 100% light temp would hit 90 and they wont be happy

Have you ever gone outside & seen a healthy watered plant dead cuz its 90? I still think you have buffer room. I've hit 99 for weeks straight when my last ac took a shit. If you can't cool your basement pulling more air into the tent from the basement wont help. You need cold air. If the inconvenience of pulling that air inside is too much for you & you dont wanna get an ac your pretty much out of options.

 

[farmer.b]

Have you ever gone outside & seen a healthy watered plant dead cuz its 90? I still think you have buffer room. I've hit 99 for weeks straight when my last ac took a shit. If you can't cool your basement pulling more air into the tent from the basement wont help. You need cold air. If the inconvenience of pulling that air inside is too much for you & you dont wanna get an ac your pretty much out of options.

Outside those temps are okay but indoors it is gonna be bad. I've had it hit high 80's and my ladies did not like it. Also worried about mites at those temps

 

[crimsonecho]

I am considering an AC but it's my last option since gonna cost ~$300 just to buy it and then the electric it will use will be more money. Not to mention finding a way to exhaust hot air outside. I was considering putting a y duct connector to connect tent exhaust fan and A/C exhaust but I am not sure if when the A/C is off, the exhaust fan will push air down the other pathway into the A/C and what effects this would have. I also have no way to pull fom an upstairs room into the tent.

Well bad news dude, you will have to get an ac if you want to use 100% power and keep the temps down. I use a 9000 btu in a medium sized, closed off room and suck air through 10 meter of aluminium duct and it works fine for me, thats all i can say, if you have the option do something like that, wall mounted split types give better performance with less electricity than portable units ime.

 

[farmer.b]

Well bad news dude, you will have to get an ac if you want to use 100% power and keep the temps down. I use a 9000 btu in a medium sized, closed off room and suck air through 10 meter of aluminium duct and it works fine for me, thats all i can say, if you have the option do something like that, wall mounted split types give better performance with less electricity than portable units ime.

Ya i think you're right gonna need to get an ac and set it up to vent cold air in and hot air out.

I have been doing alot of research and thinking about what I can change with my setup and I am going to try setting up some reflectors in the basement windows to help keep any heat out that may be finding a way in. I have black out curtains on them but still some light gets in and I think that might be part of the problem since one window gets sun most of the day. I am also gonna try venting one of the dehumidifiers directly into the tent instead of trying to dehum the whole outside room and then i can turn the other one off. Gonna switch back to passive intake or at least turn down the intake fan some think i was getting negative pressure in basement causing more heat to come in.

Hopefully implementing these things will help with temp since G gnome pointed out it does seem high for lowest basement temp. My only concern is that since i am not dehuming basement room anymore the air from intake will be higher humidity and then the dehum will run more / put hotter air into tent and and then it might cancel out the lower ambient temp.

If all that fails i will break down and buy an ac for the room. Will report back with the findings. Thanks for all the replies

 

[crimsonecho]

Ya i think you're right gonna need to get an ac and set it up to vent cold air in and hot air out.

I have been doing alot of research and thinking about what I can change with my setup and I am going to try setting up some reflectors in the basement windows to help keep any heat out that may be finding a way in. I have black out curtains on them but still some light gets in and I think that might be part of the problem since one window gets sun most of the day. I am also gonna try venting one of the dehumidifiers directly into the tent instead of trying to dehum the whole outside room and then i can turn the other one off. Gonna switch back to passive intake or at least turn down the intake fan some think i was getting negative pressure in basement causing more heat to come in.

Hopefully implementing these things will help with temp since G gnome pointed out it does seem high for lowest basement temp. My only concern is that since i am not dehuming basement room anymore the air from intake will be higher humidity and then the dehum will run more / put hotter air into tent and and then it might cancel out the lower ambient temp.

If all that fails i will break down and buy an ac for the room. Will report back with the findings. Thanks for all the replies

As a temporary solution i think using a fan directed at a slab of dry ice might work too. It is not cost effective and i am not sure how much dry ice you need to do that but it will add co2 too so its a win win. I have never done this myself and don’t know anyone who had done it either. But it might work.