Vent out air at nights in a sealed room? Excess Co2 at nighttime.

[newbplantgrower420]

I supplement co2 in my sealed room.

Plants exhale co2 at night time so my co2 ppm jumps up an extra couple hundred ppm.... much higher than needed.

So im wondering if I should start venting the grow room air out to my attic with a carbon filter with a timer to get rid of excess co2....so the plants can inhale more oxygen at night and not get suffocated by the excess co2.

Itll also help lower the humidity if needed right?

What do ya'll think?

 

[SourDeezz]

I'm in the process of doing this to my room...

 

[newbplantgrower420]

I'm in the process of doing this to my room...

whats the process like?

One recirculating carbon filter at all times and another carbon filter with a timer that turns on at night to suck in the air through the carbon filter and blow out the room?

 

[Renfro]

I like to keep that free CO2 for lights on. It doesn't hurt the plants during the dark cycle. Especially just a couple hundred PPM. If it was getting up over 2000 PPM I would have issues with it.

Now humidity is another matter. If you are having humidity issues during the dark period then venting can help if the intake air is dry, but if it's not it could make things worse. A dehumidifier is your friend.

 

[Renfro]

I like to do a lights out purge, mainly for preventing ethylene gas buildups and to help mitigate the lights off RH% spike that happens during those first 20 - 30 minutes.

 

[GreenGuy_1995]

I grow in a sealed room w/ CO2 as well - no need to vent @ lights off unless you can't keep the humidity in check.

Good Luck!

 

[newbplantgrower420]

I like to do a lights out purge, mainly for preventing ethylene gas buildups and to help mitigate the lights off RH% spike that happens during those first 20 - 30 minutes.

Just the man I was about to pm before seeing ur response.

My co2 does get to 1800ppm at nights so far at W1 flower. If it goes over 2k Ill for sure vent some out.

What do you mean a lights out purge? Quick 30m vent out?

 

[newbplantgrower420]

I grow in a sealed room w/ CO2 as well - no need to vent @ lights off unless you can't keep the humidity in check.

Good Luck!

Appreciate your take

 

[Renfro]

What do you mean a lights out purge? Quick 30m vent out?

My night temp on my controller is set lower than the day temp (during the lights on it's only a backup to the AC and is set higher like 88F so it doesn't run unless the AC were to die), so it will kick on and vent the room down 10F at lights out.

 

[newbplantgrower420]

My night temp on my controller is set lower than the day temp (during the lights on it's only a backup to the AC and is set higher like 88F so it doesn't run unless the AC were to die), so it will kick on and vent the room down 10F at lights out.

I see.

Had one more question. Lets say I want to be save on electricity.

Would it be wise to get a carbon filter and vent out into my attic at nights in a sealed room rather than using dehumids for lowering humidity during the night? I know Id be pumping out some co2 too in the process.

Also I have no issues with humidity during daytime cause of my split acs.

What would be the pros and cons to a setup like that?

 

[Renfro]

Would it be wise to get a carbon filter and vent out into my attic at nights

Venting into the attic is a big no no. When it's cold outside you will get condensation in the attic that will quickly grow a bumper crop of black mold. Install a wall vent or roof vent and take that air directly outdoors.

 

[newbplantgrower420]

Venting into the attic is a big no no. When it's cold outside you will get condensation in the attic that will quickly grow a bumper crop of black mold. Install a wall vent or roof vent and take that air directly outdoors.

will do for sure.

What do you think about the idea of getting rid of night time humidity with the carbon filter venting out compared to dehumids? It seems much more efficient unless Im missing something. 20lb tank co2 refills cost 10 bucks so Im not really worried about co2 loss with the carbon filter venting out unless its an absurd amount

 

[Renfro]

will do for sure.

What do you think about the idea of getting rid of night time humidity with the carbon filter venting out compared to dehumids? It seems much more efficient unless Im missing something. 20lb tank co2 refills cost 10 bucks so Im not really worried about co2 loss with the carbon filter venting out unless its an absurd amount

It depends on the temperature and humidity of the intake air, speed of your extraction system and how long it takes between venting cycles for #'s to climb. You definitely want a CO2 controller / environmental controller that will disable CO2 enrichment during the vent cycle.

 

[newbplantgrower420]

It depends on the temperature and humidity of the intake air, speed of your extraction system and how long it takes between venting cycles for #'s to climb. You definitely want a CO2 controller / environmental controller that will disable CO2 enrichment during the vent cycle.

I see. ya i got a co2 controller that turns off automatically at nights.

What if I was to leave a small 6 inch carbon filter to vent out the entire night cycle? What would happen then?

My logic is if I can accomplish the same thing of lowering humidity in the night cycle with carbon filter rather than a dehumidifer...why not?

Ive always ran a completely sealed room all these years and never vented out but Im curious about this hybrid sealed room strategy I read about in some old threads.

 

[Renfro]

My logic is if I can accomplish the same thing of lowering humidity in the night cycle with carbon filter rather than a dehumidifer...why not?

I hear ya, I do it all the time but my ambient RH% is generally super low. That said I have to be on point and watching the humidity, if it's not low then I have to run the dehu instead.

It all depends on the humidity of the air you are pulling in.