quick venting fan question...

I'm finishing up a "room" in a closet (using half the space under the full shelf), and for now I'm going to vent the room out into the the larger closet space (if I decide to, I can vent directly up into the attic). I'm pretty sure if I leave the outer closet doors open at both ends a few inches, there should be sufficient fresh air moving through the whole area, and this is an entirely CFL set up, so heat should not be an issue.

I have it set up with a bathroom fan as the exhaust fan -- any reason that would not be a good idea? Has anyone used one? Specifically wondering about leaving it on 24/7, would burn out quickly?

It's a cheap one ($14) but rated at 50cfm and the space is approximately 28 cubic feet, would that be a sufficient air exchange? There will be additional fan(s) as needed to circulate air within the grow space, the primary question is just about moving fresh air through.

What do you think?

I used a bathroom fan for a few years, I even slowed it down with a cheap ceiling fan light dimmer, I also am a fan of venting into attics, just make sure your Attic has good vents on top of your roof line to let the air breath out of the space well

Tim Fox said:

I used a bathroom fan for a few years, I even slowed it down with a cheap ceiling fan light dimmer, I also am a fan of venting into attics, just make sure your Attic has good vents on top of your roof line to let the air breath out of the space well

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Thanks for the info -- especially about the light dimmer switch, that's a great idea! My attic is well vented, and has a thermostat driven fan in the summer. Bathroom fans can be inexpensive and easy to set up, but they are for the most part kind of loud (the really expensive ones are quieter). It's not an issue, just obnoxious.

You got it those cheap ones will run a long time, and they will get nice and quiet with the light dimmer, your all set

Humanrob said:

Thanks for the info -- especially about the light dimmer switch, that's a great idea! My attic is well vented, and has a thermostat driven fan in the summer. Bathroom fans can be inexpensive and easy to set up, but they are for the most part kind of loud (the really expensive ones are quieter). It's not an issue, just obnoxious.

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I would also recommend the dimmer as most of the cheap ones can be quite loud unless you slow them down. Also a fan of venting into attics.

Just a quick follow up to share what I learned.

First, if you are going to want to utilize the fans full capacity, you need to get a fan dimmer not a light dimmer. I didn't know the difference but my experience with the products I got is that the light dimmer doesn't put out enough watts (amps?) on its highest setting to run the fan at nearly its full speed.

The "3-speed" fan switch I tried next was made for a ceiling fan, and again the amps (watts?) were not well matched for a bathroom fan and the "low" setting barely rotates the fan, and "med" and "high" are almost indiscernible from each other.

But the bottom line is that after testing against the heat the lights make, my space turned out to be at the outer edge of a bathroom fan's capability, so it will never be run at less than full speed anyway.

I'm sure these fans are a good solution for many a true "micro" grow (I guess my half closet is not by definition really micro), and using a light dimmer would probably be OK if the space was small enough to be serviced with the diminished airflow the switch would induce.

Thanks again for all the help, and learning and sharing what we've learned is what this is all about.

A triac is most often used when dimming AC motors

they get a little spendy, but well worth it....

i used the same type of 3 speed fan switch for mine, and noticed the same results... i was running at full speed for the light that just went out on me, 400w mh. now im using the low setting for these 2 little bulbs just to keep fresh air moving thru the box... heat is non existant. lol. the low speed is just right for the situation, but medium and high its hard to tell the difference... hope its not going to mess the fan up, still holding out on making an order that will include a proper fan controller :/

The triad/variac type speed controller I am using is sold thru amazon for 68 dollars works fantastic

Abiqua said:

A triac is most often used when dimming AC motors

they get a little spendy, but well worth it....

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I picked up the same one on amazon two months ago. Much more quiet than the 'speedster' type too.

Tim Fox said:

The triad/variac type speed controller I am using is sold thru amazon for 68 dollars works fantastic

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This is the money trap I've fallen into a couple of times already. If I had heard that there was a $68 speed controller vs. the $20 one I bought, I might still have tried the $20 one first (unless someone had explicitly told me it would not work). Without that knowledge I've bought two $20 ones, and $40 out of pocket later I still don't have a switch that does what I want it to, so now the $68 one is sounding pretty reasonable.

Basically the same situation happened with my whole CFL setup -- LED's sounded too expensive, but I've spent at least 2/3's of what it would cost for an LED setup on CFL bulbs and hardware, and now I'm going to end out starting over with LED's anyway.

It can be hard to explain to a newbie exactly why spending more upfront can be the totally better way to go, especially when the newbie doesn't know how deeply they are going to love growing (or not…). You can't put a price on it, but I probably have as much invested emotionally in the plants success as I do monetarily. I guess I really needed another hobby! This is like an amalgam of a fish tank (indoor controlled habitat), a greenhouse (contained plant nursery)… and home brewing beer (patience and time = altered consciousness)!

Humtheanrobsame choices said:

This is the money trap I've fallen into a couple of times already. If I had heard that there was a $68 speed controller vs. the $20 one I bought, I might still have tried the $20 one first (unless someone had explicitly told me it would not work). Without that knowledge I've bought two $20 ones, and $40 out of pocket later I still don't have a switch that does what I want it to, so now the $68 one is sounding pretty reasonable.

Basically the same situation happened with my whole CFL setup -- LED's sounded too expensive, but I've spent at least 2/3's of what it would cost for an LED setup on CFL bulbs and hardware, and now I'm going to end out starting over with LED's anyway.

It can be hard to explain to a newbie exactly why spending more upfront can be the totally better way to go, especially when the newbie doesn't know how deeply they are going to love growing (or not…). You can't put a price on it, but I probably have as much invested emotionally in the plants success as I do monetarily. I guess I really needed another hobby! This is like an amalgam of a fish tank (indoor controlled habitat), a greenhouse (contained plant nursery)… and home brewing beer (patience and time = altered consciousness)!

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I made all the same choices that you did early on, I bought a bathroom fan, I bought an inline fan, I bought a carbon filter that was too small, I bought 180 dollars of cfl and or cree household bulbs, just like you did, but what is the differance, I bought all those things thru home depot and amazon, I saved my reciepts and i saved the wrapping and boxes, I ended up being able to get my money back on ALL of it, and it was really relieving to be able to learn and exchange, I did laugh a few times at the return lines. but they never questioned me and they were always nice, I do kinda wish that I could return my 300 watt mars, but in the end the top grows I have seen with cxa3070 cobs they throw in some smaller red and or blues to fill out the spectrum, so I am just going to run the mars along with 2 cxa3070s mounted to both ends, so I luck out i guess , so many times I stepped in shit along the way, but working with home depot and Amazon.