Still in first grow, climate control challenges

[NorthernLights_420]

So I bought a new AC Infinity 6" fan & filter tonight, and I'll relegate the 4" to a drying tent (when they're ready!). Also found a dehumidifier beg enough for the closet so I'll lower the closet's RH as well, and the big fan will help the inside tent air.

Thanks for listening on upgrading. All you can do at this point. That fan should be plenty enough to help your situation. Top of the line gear you ordered! Congrats and I can't wait to hear the update when it arrives. Costs us all money to grow unfortunately. But we all get it back if we help each other and invest in the right equipment. Rep given to you grower friend!

 

[MI_sterGreen]

My exhaust right now is (filter then 4" fan inside of tent) exhausting out top of tent thru 4" duct. Also have a 4" intake fan at the bottom of the tent. The tent is in a walk-in closet, so the air outside the tent is only marginally cooler (~5*F) than the air inside the tent. The RH outside the tent is about 10% lower than inside the tent.

If the closet is closed and you're pumping the hot air out of the tent back into the closet, a bigger fan most likely won't help. Same with dehumidifier. You're really going to superheat that closet with that in there. They pump dry very warm air out

 

[NorthernLights_420]

If the closet is closed and you're pumping the hot air out of the tent back into the closet, a bigger fan most likely won't help. Same with dehumidifier. You're really going to superheat that closet with that in there. They pump dry very warm air out

I agree with this. You shud pull air from a different room and exhaust else where. If your pulling air from your closet or exhausting air into your closet that will definently not help your temps much.

 

[NorthernLights_420]

Dropping your light schedule down to 18/6 will save you about 60 hours of your light running per month. And it will help lower temps a little bit too on top of the energy savings.

 

[ms48130]

If the closet is closed and you're pumping the hot air out of the tent back into the closet, a bigger fan most likely won't help. Same with dehumidifier. You're really going to superheat that closet with that in there. They pump dry very warm air out

yeah, the new exhaust fan is to arrive Saturday, but I got a good sized dehumidifier today. I fired up the dehumidifier outside the tent (walk-in closet, but open on both ends, one end to the master bath, and the other end to the laundry room (which is where I'll be setting up my drying tent) so the dehumidifier can serve both rooms (closet AND laundry room).

The dehumidifier was able to get the outside tent RH down to 45% rather nicely, but as you said, it heated up the closet (with both closet doors closed) to 89*F. When I opened both closet doors to the adjacent rooms (both have fresh A/C ducts as well as the closet itself), the temp got down to 83*F. These are OUTSIDE OF TENT conditions, which it seems to me is "the best possible" environmental conditions, since inside the tent can't be better than outside the tent. No windows, no other vents, no possibility of any other environmental impact.

EDIT: with one possible item for impact: as @NorthernLights_420 suggested, I can drop my lighting schedule. I have a photoperiod in the tent that I've been manifolding, and I will very soon flip to 12/12, which might help some with the inside tent conditions, but STILL, can't be better than outside tent. Agree, or not? Thanks

 

[MI_sterGreen]

yeah, the new exhaust fan is to arrive Saturday, but I got a good sized dehumidifier today. I fired up the dehumidifier outside the tent (walk-in closet, but open on both ends, one end to the master bath, and the other end to the laundry room (which is where I'll be setting up my drying tent) so the dehumidifier can serve both rooms (closet AND laundry room).

The dehumidifier was able to get the outside tent RH down to 45% rather nicely, but as you said, it heated up the closet (with both closet doors closed) to 89*F. When I opened both closet doors to the adjacent rooms (both have fresh A/C ducts as well as the closet itself), the temp got down to 83*F. These are OUTSIDE OF TENT conditions, which it seems to me is "the best possible" environmental conditions, since inside the tent can't be better than outside the tent. No windows, no other vents, no possibility of any other environmental impact.

EDIT: with one possible item for impact: as @NorthernLights_420 suggested, I can drop my lighting schedule. I have a photoperiod in the tent that I've been manifolding, and I will very soon flip to 12/12, which might help some with the inside tent conditions, but STILL, can't be better than outside tent. Agree, or not? Thanks

Agree. The tent can only mimic the environment that surrounds it. You're headed in the right direction though it sounds like. I usually run lights off during day since its the warmest and then on at night when it gets cooler.

 

[ms48130]

Agree. The tent can only mimic the environment that surrounds it. You're headed in the right direction though it sounds like. I usually run lights off during day since its the warmest and then on at night when it gets cooler.

Generally I’d agree with that, but my wife & I like it cooler while we sleep, so it’s actually set cooler at night!

 

[Death The Cultivator]

There's no reason you couldn't flower at 85f/60% rh. You're buying all this stuff when an IR thermometer and a reliable humidity sensor could save you headaches.

Vapor Pressure Deficit VPD Calculator - Dimlux Lighting - The Best Grow Lights

Vapor Pressure DeficitCalculator Calculate both Room VPD and Leaf VPD automatically Just enter the value below to generate the VPD values for your room and your plants. You’ll need to know the room’s temperature, relative humidity, and the plant’s temperature. We recommend calibrating your...

www.dimluxlighting.com

You measure the VPD through humidity, leaf surface temperature with an IR gun, and ambient temperature. It's harder to tell what needs to be changed if you can't reliably measure VPD.

With an IR gun and that chart you would have discovered you didn't need to spend any money. 85f/60rh is within VPD range of 1.2-1.6kpa for flowering. With proper airflow and air exchange. You're room could be cooler but you aren't in any danger.

Imo, return the humidifier/fan/filter and get an IR gun. You might not need any appliances or maybe just a humidifier to maintain about 50% humidity. It's only a 15% difference from veg to flower for humidity if your heat is constant.

6 inch fan is overkill for a 2x2, a 4 inch is really too much still. Less than 100cfm will work in that space.

 

[ms48130]

There's no reason you couldn't flower at 85f/60% rh. You're buying all this stuff when an IR thermometer and a reliable humidity sensor could save you headaches.

Vapor Pressure Deficit VPD Calculator - Dimlux Lighting - The Best Grow Lights

Vapor Pressure DeficitCalculator Calculate both Room VPD and Leaf VPD automatically Just enter the value below to generate the VPD values for your room and your plants. You’ll need to know the room’s temperature, relative humidity, and the plant’s temperature. We recommend calibrating your...

www.dimluxlighting.com

You measure the VPD through humidity, leaf surface temperature with an IR gun, and ambient temperature. It's harder to tell what needs to be changed if you can't reliably measure VPD.

With an IR gun and that chart you would have discovered you didn't need to spend any money. 85f/60rh is within VPD range of 1.2-1.6kpa for flowering. With proper airflow and air exchange. You're room could be cooler but you aren't in any danger.

Imo, return the humidifier/fan/filter and get an IR gun. You might not need any appliances or maybe just a humidifier to maintain about 50% humidity. It's only a 15% difference from veg to flower for humidity if your heat is constant.

6 inch fan is overkill for a 2x2, a 4 inch is really too much still. Less than 100cfm will work in that space.

Fortunately I do have an IR gun (industrial Milwaukee brand) which I use for my grill. Not sure if they are made with lower temp ranges which might be better suited. I had to buy another fan & filter anyway for a drying tent, so my 6” is just oversized for my grow tent. Also, I bought the dehumidifier used, and i’ll Want that for drying as well.

Thank for the info/relief!