High temp and low humidity problems in my tents

illmatik

Well-Known Member
I have a 4x4 and 4x8 tent in a bedroom in sunny California.

The 4x4 has a 4 inch exhaust fan and the 4x8 has a 6 inch exhaust fan. Both fans are exhausting directly out of the the house through a window. Intake is passive through the bottom tent flaps. The home has central cooling, and the ambient temperature of the bedroom is around 76*F.

The coolest I can get my grow tents is about 84*F with lights on, by running the exhaust fans at full speed. My RH is about 40% which puts my VPD in a bad place and the plants are showing it.

A humidifier is not making a dent on the RH since there is so much air being moved, but if I turn the fan down, my temps increase. I've tried a 1 gallon humidifier both inside and outside of the tents. I have a couple pond foggers arriving today that I will try.

How can I increase the RH in the tent with so much air circulation? I know this is really challenging with the high level of air circulation and my dry climate. But I'm hoping there is a way without having to get additional cooling for my room.
 
I have a 4x4 and 4x8 tent in a bedroom in sunny California.

The 4x4 has a 4 inch exhaust fan and the 4x8 has a 6 inch exhaust fan. Both fans are exhausting directly out of the the house through a window. Intake is passive through the bottom tent flaps. The home has central cooling, and the ambient temperature of the bedroom is around 76*F.

The coolest I can get my grow tents is about 84*F with lights on, by running the exhaust fans at full speed. My RH is about 40% which puts my VPD in a bad place and the plants are showing it.

A humidifier is not making a dent on the RH since there is so much air being moved, but if I turn the fan down, my temps increase. I've tried a 1 gallon humidifier both inside and outside of the tents. I have a couple pond foggers arriving today that I will try.

How can I increase the RH in the tent with so much air circulation? I know this is really challenging with the high level of air circulation and my dry climate. But I'm hoping there is a way without having to get additional cooling for my room.
Just an amateur here but maybe your lights are the problem' maybe you need less but a more powerful one.
 

DankMoss

New Member
I have a 4x4 and 4x8 tent in a bedroom in sunny California.

The 4x4 has a 4 inch exhaust fan and the 4x8 has a 6 inch exhaust fan. Both fans are exhausting directly out of the the house through a window. Intake is passive through the bottom tent flaps. The home has central cooling, and the ambient temperature of the bedroom is around 76*F.

The coolest I can get my grow tents is about 84*F with lights on, by running the exhaust fans at full speed. My RH is about 40% which puts my VPD in a bad place and the plants are showing it.

A humidifier is not making a dent on the RH since there is so much air being moved, but if I turn the fan down, my temps increase. I've tried a 1 gallon humidifier both inside and outside of the tents. I have a couple pond foggers arriving today that I will try.

How can I increase the RH in the tent with so much air circulation? I know this is really challenging with the high level of air circulation and my dry climate. But I'm hoping there is a way without having to get additional cooling for my room.

I had the opposite problem in flower humdity was two high.

I would advise that if you turn you fans down and your exaushst on full extraction maybe try two exhaust fans at it will help extract hot air.
youll defo want two humidfers as well but on in tent and one outsid eof it to help balance the humidty in room aswell as tent.
 

lime73

Weed Modifier
Turn exhaust fan on low. Do you have neg pressure?

or Fill tent with plants, leaves, fill tent floor with big bushy plants. :bigjoint:
 

illmatik

Well-Known Member
Just an amateur here but maybe your lights are the problem' maybe you need less but a more powerful one.
I have two 620W Geek Beast Pros in the 4x8 and one 480W Kingbrite in the 4x4. They're not even at full power and I'm having heat issues.
 

coreywebster

Well-Known Member
84f isn't a heat problem with LED.
But if you use a swamp cooler in the room it will lower the room temp a few degrees and raise humidity.
At the same time lower fan speed.

Or turn your home AC up and your extraction down.

I don't think a 1gal humidifier would be close to been enough in a vented room.
 

illmatik

Well-Known Member
84f isn't a heat problem with LED.
But if you use a swamp cooler in the room it will lower the room temp a few degrees and raise humidity.
At the same time lower fan speed.

Or turn your home AC up and your extraction down.

I don't think a 1gal humidifier would be close to been enough in a vented room.
Would adding an intake fan help with being able to keep temps low with lower fan speed?

I was looking into a swamp cooler, but hate to add something to my system that would need to be refilled constantly. Right now my 55gallon res lasts me 2+ weeks before a refill. I suppose I could find a way to plumb a water source to the swamp cooler but if I can find a way to get my RH up and temps a little lower without using one I'd be much happier.
 
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PissingNutes

Active Member
I get 10% or LL humidity in winter. I got a 3000sp.ft humidifier that I ducted direcly to my tent that sits up on sawhorses with humidifer under blowing up in tent). 2 refills daily for 5 gallons total and was lucky to get 35% when watering. Also had another 2500 sq. ft. in the room pumping total of about 10 gallons a day. Hope that helps.
 

Towelie29

Well-Known Member
I have a 4x4 and 4x8 tent in a bedroom in sunny California.

The 4x4 has a 4 inch exhaust fan and the 4x8 has a 6 inch exhaust fan. Both fans are exhausting directly out of the the house through a window. Intake is passive through the bottom tent flaps. The home has central cooling, and the ambient temperature of the bedroom is around 76*F.

The coolest I can get my grow tents is about 84*F with lights on, by running the exhaust fans at full speed. My RH is about 40% which puts my VPD in a bad place and the plants are showing it.

A humidifier is not making a dent on the RH since there is so much air being moved, but if I turn the fan down, my temps increase. I've tried a 1 gallon humidifier both inside and outside of the tents. I have a couple pond foggers arriving today that I will try.

How can I increase the RH in the tent with so much air circulation? I know this is really challenging with the high level of air circulation and my dry climate. But I'm hoping there is a way without having to get additional cooling for my room.
Humidify the room that the tents are in instead of the tent itself, possibly upgrade the humidifier if it isnt doing the job or run a second one. Also consider upgrading your exhaust fan in the 4x4 to a 6" fan. The 4x8 might need an intake fan or a second exhaust fan. The AC Infinity T6 fans can link to another S6 fan for dual exhaust fans. If your exhaust duct run is really long, get some inline booster fans. Cheers :)
 

illmatik

Well-Known Member
Just pulled the trigger on a pair of AC Infinity T6 and S6 fans. I'll use them as exhaust and intake in the 4x8 and I can swap over the 6inch over to the 4x4. Hopefully with a few pond foggers I can get the RH of the room up and the increased circulation at lower fan speeds should help as well.

Thanks all
 

Towelie29

Well-Known Member
Just pulled the trigger on a pair of AC Infinity T6 and S6 fans. I'll use them as exhaust and intake in the 4x8 and I can swap over the 6inch over to the 4x4. Hopefully with a few pond foggers I can get the RH of the room up and the increased circulation at lower fan speeds should help as well.

Thanks all
I'm not entirely sure if you can link them to be intake and exhaust seperately, but you could try. As long as it isnt sucking the walls in too much then it should be okay. If that doesn't work you can try doing two exhausts but I don't know how well that will work with a passive intake. Amazon is great though so if it doesnt work for you, you can always send one back :) You could also run the S6 on its manual fan speed controller until it's at the right CFMs for the tent. From what I've read the intake should be less CFMs than the exhaust.
 

PissingNutes

Active Member
Humidify the room that the tents are in instead of the tent itself, possibly upgrade the humidifier if it isnt doing the job or run a second one. Also consider upgrading your exhaust fan in the 4x4 to a 6" fan. The 4x8 might need an intake fan or a second exhaust fan. The AC Infinity T6 fans can link to another S6 fan for dual exhaust fans. If your exhaust duct run is really long, get some inline booster fans. Cheers :)
Sorry but that's just wrong, it's cool the air in the room. If his small humidifier won't do the tent you think it will do the room? And if you've had to create lots of humidity you would know you have to carry lots of water which doing the room makes it worse and possibly damage/mold the area.
 

Towelie29

Well-Known Member
Sorry but that's just wrong, it's cool the air in the room. If his small humidifier won't do the tent you think it will do the room? And if you've had to create lots of humidity you would know you have to carry lots of water which doing the room makes it worse and possibly damage/mold the area.
Humidistat
 

Towelie29

Well-Known Member
Right a humidistat in the room connected to a one gallon humidifier will fix his problem.
I suppose it would have to be that way for small plants. But if the RH is around 40-44% in the room and there are large plants in the tent. The humidity in the tent will rise up to 60-70% RH if you don't set the AC Infinity fans lower than that.
 

PissingNutes

Active Member
Yeah but he won't get over 25% in the room with that small humidifier or a pond mister than barely humidifies a margarine container. Buying sensors won't solve much here.
 
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