The Ultimate Odour Control Thread

[McStrats]

This is true. Carbon is ruined quickly by moisture. A poly-felt wrap around the carbon canister can help quite a bit though.

This stuff is polyester filter media. Your local HVAC place will have tons of it. Wrap it around your carbon canister. It will slow the air down and give you more dwell time. It will also trap a lot of moisture. Same principle as a face mask for moisture droplets.

 

[nygaff1]

800 x 60 = 48,000 / 256 = 187.5 ACH if running full - running at 25% you still have around 49 ACH. There isn't a carbon filter out there that can keep up with that. For proper carbon "dwell time" ACH should be around 10-15. The amount of air you have rushing through that carbon filter isn't allowing it to scrub the odor properly.

But the 800cfm rating of the fan is rated without additioal load. The carbon filter reduces it 25%.

But still, the math doesn't line up. Any suggestions? I am unable to keep my humidity below 55% during lights out without the fan on at 40%.

But also, it's not like the filter can't keep up all day, it's just for a few hours before lights off. Once they go out the smell is gone.

 

[nygaff1]

This is true. Carbon is ruined quickly by moisture. A poly-felt wrap around the carbon canister can help quite a bit though.

They don't work well in high humidity.

It's not a high humidity situation.

The lung room is under 40% at the moment. 45% in the tent during lights on and 55%(+) during lights off. The smell is only noticeable a few hours before the lights go out.

 

[McStrats]

But the 800cfm rating of the fan is rated without additioal load. The carbon filter reduces it 25%.

But still, the math doesn't line up. Any suggestions? I am unable to keep my humidity below 55% during lights out without the fan on at 40%.

But also, it's not like the filter can't keep up all day, it's just for a few hours before lights off. Once they go out the smell is gone.

The thread is about odor control. Sizing the cfm of the fan to give the right amount of ACH is a matter of simple well established math.

Controlling humidity doesn’t involve your carbon filter. That isn’t what it is designed for.

You might need a dehumidifier.

 

[nygaff1]

The thread is about odor control. Sizing the cfm of the fan to give the right amount of ACH is a matter of simple well established math.

Controlling humidity doesn’t involve your carbon filter. That isn’t what it is designed for.

You might need a dehumidifier.

Yes, I am fully aware. I didnt come here to ask "help me size my fan setup!" or " help me soze my dehumidifier!"... I answered the two questions that were asked in response to my question about the timing of my odor issue running like clockwork...

 

[McStrats]

Yes, I am fully aware. I didnt come here to ask "help me size my fan setup!" or " help me soze my dehumidifier!"... I answered the two questions that were asked in response to my question about the timing of my odor issue running like clockwork...

You said the math doesn't line up. Please share exactly what math you are using. I'm a novice grower but my day gig is Engineer. I can promise you math is the answer to all things air movement-related.

If everything is sized correctly you won't have any odor. As long as your carbon filter fan isn't on a timer with the lights you shouldn't see a significant difference in odor at any point in the day. A 350 cfm fan (even with losses taken into consideration) is still way too large for that space. The taper on those fan controllers isn't all that accurate either. A VFD is the only accurate way to dial back a fan to 25% and they are expensive. Try a smaller fan setup with less cfm. My grow area is double yours and I use a smaller fan than you are using. I have zero odor issues.

Put a dehumidifier in the lung room if you feel the humidity is too high.

 

[nygaff1]

You said the math doesn't line up. Please share exactly what math you are using. I'm a novice grower but my day gig is Engineer. I can promise you math is the answer to all things air movement-related.

If everything is sized correctly you won't have any odor. As long as your carbon filter fan isn't on a timer with the lights you shouldn't see a significant difference in odor at any point in the day. A 350 cfm fan (even with losses taken into consideration) is still way too large for that space. The taper on those fan controllers isn't all that accurate either. A VFD is the only accurate way to dial back a fan to 25% and they are expensive. Try a smaller fan setup with less cfm. My grow area is double yours and I use a smaller fan than you are using. I have zero odor issues.

Put a dehumidifier in the lung room if you feel the humidity is too high.

Again, I have 0 issue with odors except for 2 hours of every day. I understand the concepts you are suggesting however it doesnt explain why my system works 100% sans that small daily time frame.

I never mentioned humidity. It is not my issue, unless there is some biological processin the plant I am missing where humidity spikesright before sundown. I have a 50l dehumidifier in my lung room.

 

[McStrats]

Again, I have 0 issue with odors except for 2 hours of every day. I understand the concepts you are suggesting however it doesnt explain why my system works 100% sans that small daily time frame.

It does. You have too many cfm to allow the carbon to properly have adequate "dwell time". Btw, Dwell time and ACH are not "concepts". They are engineering science.

I never mentioned humidity. It is not my issue, unless there is some biological processin the plant I am missing where humidity spikesright before sundown. I have a 50l dehumidifier in my lung room.

I misunderstood the humidity thing then.

 

[Rsawr]

Guys, we don't argue and call names here. Cool it please.

 

[coreywebster]

Guys, we don't argue and call names here. Cool it please.

Are you a new mod?
Waa wondering who filled the position

 

[McStrats]

What about temperature control and humidity

It's hard to combine all 3 functions (temp, moisture, odor) into a carbon filter that is only designed for odors.

 

[McStrats]

I notice that quite a few people try to combine multiple functions into their carbon setup. The problem with that is carbon is designed to do only one thing, and in order to do that properly....sometimes those purposes are at odds with each other. You can run your exhaust fan on high to cool the space...but your carbon can't keep up sometimes..so you just end up blowing cannabis odor all over the place. One way to overcome this is by running a 6" carbon filter with a 4" fan. The increased resistance can allow you to find a sweet spot. I run a box fan at full speed right across the lights. This works incredibly well. It allows me to dial back the exhaust to have the right amount of dwell time of odor in carbon.

 

[McStrats]

@MATTYMATT726 I thought you might like this conversation.

 

[nygaff1]

Update to my problem from back in march^. The answer was indeed the lack of performance from the AC Infinity 8"XL filter. The MFG. Specs rate it for 930cfm, which is either bullshit or only when used as a scrubber.

I replaced it with a new Phat 8"x39" on the same programming schedule and cfm ratings that were pulling through the AC Infinity. It's the extra 31lb of carbon and almost foot longer bed that does the trick. I should have just gone with the phat from the get go...