Tent Extraction: Filter inside, fan outside?

[McSnappler]

Hey guys, just a really quick one. I've tried searching but for some reason the word "outside" is considered too common to search for!

I've got the smallest BudBox, 75cm x 75cm x 1m high, and I'm about to start flowering UK Cheese.

Because I'm major concerned about smell, I got a hugely oversized fan, and the carbon filter to match. The plan was to have both attached together, with ducting taking the cleaned air into a crawl space next to the room.

My problem is the filter including flange is about 66cm, which doesn't leave the 28cm or so needed for the fan too.

My idea now, aside from taking the filter back and getting the smaller one, is to have the filter, into the ducting, with the fan inside the crawl space itself. You're probably talking about 2-3m of ducting between can filter and fan.

Would this hamper the performance of the filter?

I'm not TOO bothered about extra drag in terms of ventilating the tent, as the fan is literally tough enough to deal with a row of them if it needed to, but my primary concern is clean, stink free air.

Any help massively appreciated as always!

 

[FreezerBoy]

Nothing wrong with the fan being in another room as long as you've got the power. Added benefit to the crawl space is it will greatly muffle the sound of the fan and rushing air.

 

[McSnappler]

Thanks FreezerBoy.

Another quick question if I may?

It's just occurred to me that I could fit both items in the tent, by mounting the filter and fan at right angles to one another, with a short 90 bend of ducting in between. I have read that a 90 degree bend just before the fan causes massive drag though.

Which do you think would be preferable in terms of filter/fan performance?

Good point about the sound absorption when using the crawl space. Could be a swaying factor regardless of which is 'better'.

 

[FreezerBoy]

Well, now you're in redgreenry territory Ventilation 101

Any curve will reduce flow. The smaller the radius the greater the drag. Flex ducting creates more drag than hard (smooth) ducting. But if you've "got a hugely oversized fan, and the carbon filter to match" I'd think you'll be OK.

Just to confuse things as much as possible, while it's better to pull than to push, you could reclaim the space now dedicated to the filter system by placing both fan and filter in the crawlspace. With the filter at the end of run, it would act as a muffler. Course, you'd have to go into the space every year or so to do filter maintenance.

 

[McSnappler]

Just to confuse things as much as possible, while it's better to pull than to push, you could reclaim the space now dedicated to the filter system by placing both fan and filter in the crawlspace. With the filter at the end of run, it would act as a muffler. Course, you'd have to go into the space every year or so to do filter maintenance.

Going on previous threads, I think I would get crucified by the majority for doing it that way!

Many thanks again for your input dude.