DIY Struggling to find a solution to Portable AC exhaust smell. Any advice appreciated.

[some_guy_]

Have a single hose Portable AC that sits in my 5x10 grow tent, that sits in a garage.

It takes in smelly weed air from in the tent, cools it, and exhausts weed smelling hot air directly outside.

I have a scrubber in the tent, doesn't seem to do much to stop the exhausted air from smelling.

Any tips?

I know I can't connect a carbon filter to the ac exhaust as any backpressure can ruin the coil in the AC and it might stop working.

Things I've considered:

-Connecting a carbon filter to an inline fan to the AC exhaust.
But I'm assuming there's some issues here as well?
Inline fan might not be powerful enough, the AC exhausted air might be too hot for the inline fan?

-Exhausting from the tent to the garage in which my tent sits, and exhausting out of the garage with several inline fan and filters to the outside world.
Some problems include hot garage, may need several inline fans to exhaust enough heat out to keep on top of what heat the ac is pumping out.

-exhausting the ac into a small box that has ONA gels inside so before it gets to the outside world, the ac exhaust flows over the ona gel?

-exhausting the ac into a box with two scrubbers that exhaust into the outside world?
Some problems that might have are the scrubbers in a sealed tight box with the hot ac exhaust might not work well or a fire hazard. ||

Does anyone have any suggestions? Im at my wits end.

Worst comes to worst I can cool the whole garage instead but i dont know if my portable AC is strong enough to cool an entire uninsulated garage.

Thanks everyone

 

[Cave Dirt Cody]

Maybe get a inline booster fan for the filter?

 

[Cave Dirt Cody]

Here’s a six inch with speed control. Experiment with placement and speed. Should help.

 

[JP1]

Carbon filter attached to the exhaust fan should work fine. Maybe you're not getting enough exhaust? Do you get negative pressure in the tent with the exhaust fan turned all the way up?

 

[Drownomatic]

Go to the home center buy one of those large plastic tubs. pipe the hose in, then another hose outside.

Fill it with charcoal briquettes, and spray them with fabric softener.

This was how we did DIY filters in the 70's

 

[Xmaggle]

Use an 8" fan and matching high quality carbon filter inside the tent. Pay attention to the filter's stated capacity versus the fan's stated CFM. In other words, avoid combining a filter that can handle 600 cfm with a fan that is pumping 750 cfm. Ideally, you want the fan running a little slower than the max capacity of the filter. Set up properly, your tent will now always have slightly sucked-in walls, because you are running your fan 24/7, and the fan exhaust is the only place that air is exiting the tent. Leave the open end of the exhaust as elevated as possible. Let the hot filtered air rise up and away from the tent. Next, set up your portable AC outside of the tent to exhaust heated air outside the garage. Place the AC unit to blow directly toward/onto the bottom of the tent.

With that setup, your single hose PAC is exhausting hot air outdoors, blowing cold air toward the base of your tent. Your tent fan is generating negative pressure, causing the tent to suck in the cold air, and is exhausting toward the ceiling of your garage. The inside of your tent won't be as cool as when the AC was inside, but it's still drawing in the provided cool air, and barring extremely high ambient air temp or humidity, things will be cool enough to keep the filter effective. (Heat and humidity interfere with carbon filtration of air.)

For much of your grow cycle, that setup will handle the smell entirely. Obviously, the later parts of flower cycle are when you will find out the system's limitations. Keep the tent zipped up as close to always as possible. The smell will tend to accumulate up high in your garage, where you are exhausting from the tent. Your PAC is doing all its intake, cooling and exhausting close to the ground. Some times, with some strains, that 8" filter might be just fine for a tent of that size. Other strains, the kind of girls who smell the best, might overwhelm it toward the end.

I spent a couple of decades pulling my hair out the last 2 or 3 weeks of every flower cycle, when whatever odor control I was doing was not quite enough. Maybe I'm a little slow, but I finally figured out the importance of engineering in a little extra capacity in the odor control system. Where people recommend a 4" fan and filter, use a 6" pair (again properly balanced like I mentioned above). Where they recommend a 6", go with an 8". The area of an 8" circle is nearly double a 6" circle, which is double a 4" circle. I run a 6" setup in a 4' X 4' tent. The I run an 8" setup in the room that holds the tent. No smells leak from the tent until about mid-flower. No smells leak from the room containing the tent at all, unless i get careless and leave the door open for awhile. The only time I really smell anything outside the room is when I am trimming inside the room at harvest. Trimming/Harvesting always seems to overwhelm any smell control system, but at the same time, for four plants in a 4' X 4' tent, the burst of smell only lasts half a day or so and then the filtering systems seems to catch up as the chopped up material begins to dry.

One last thing: Avoid cheap filters. Some of the cheapest have visibly unsealed (or poorly sealed) seams. Stinky air can actually go around the carbon through those seams. You don't necessarily need the most expensive filter, but cheap crap oftens turns out to be cheap crap.

 

[Blue_dreamer]

Your AC shouldn't be exhausting smell. The AC part and the condenser part in the back shouldn't be exchanging any air.
It sounds like your AC unit isn't sealed very well. I would suggest you take the cover off of the AC , and work on sealing up the front section from the back section better. Maybe use some silicone caulk or expanding foam. There should be some foam insulation already, but it may be letting enough air past that its causing the smell.