the dryer hose is connected to the fan bone?

Okay ive seen a couple of ways to vent air. One is a charcoal filter stuck on a "can" fan stuck on a dryer hose connecected to another room.

Another way ive seen is the charcoal filter connected to the fan conected to the 6 inch flask opening on the HPS light (both sides) and then connected to another room

Are there any advantages to the first or second setup? sorry if its not clear. I tried my best to describe it the best of my memory.

Also can a HPS light use a MH bulb or is this imposible?

 

The only thing is that a single filtering may not be enough! Example: set your filter on th' floor to one side. run the hose through the lite or whereever to the other side of the room near ceiling, the point is to get the most circulation. this will filter the air over and over. This is just odor control advice, you still need to exhaust the room.

 

In line extractor fans can be connected directly to your reflector via a hose. These lights are excellent as most of the heat comes from your bulb you are removing the heat at its source. This enables lights to be a lot closer to your plants. Although this system is probably the best they are expensive and somewhat more complicated to set up. For a first grow keep things simple and don't spend a fortune on equipment. Vent the room with a simple extractor fan, invest in a charcoal filter if you wish. Maybee a cheap ozone generator could be a good option.

 

Unless yer operating a warehouse, I would never recommend an ozonator.
For small spaces, an ionizer will work just as well as an ozonator, and it's completely safe. You can't overdo it with ionizers, but if you overdo it with an ozonator, you can die.

 

If you are going to use only one fan, you definately should hook it up to the hood. As someone else wrote, it will take the heat out from the source (the bulb) but it will aslo help keep the bulb cooler which will help it to last a lot longer.
As for dryer hoses on any other kind of flexible ducts, I try to shy away from them as much as possible. I prefer to use sheet metal ducts whenever possible as much as possible. They are more challenging to install but they don't conduct noise as much as the flexible kind and they allow for a freer airflow and less strain on your fan for more efficiency. You can use a combination of sheet metal ducts and flex stuff if using only sheet metal ducts is too much a challenge for you.

I am a heating/cooling/insulation trademan and I have to say the flexible ducts are used way too much by growers.

Make sure the air enters the grow at the bottom of the grow near the floor and as it gets heated, it raise and gets exausted via the hood.

You can exaust it into the house in winter to help keep the house heating bill down and you can throw it out the window in the summer to help keep the house cooler and save on your A/C bill.

Me, I consider the best system to be a completely sealed room where you take the air from the outside directly to the hood and to be thrown back outside. The room can be cooled by an A/C unit inside the grow. Smell is kept down by recirculating the grow air into a scrubber.
However, you can't build a system like this without incorporating a CO2 injection system but we are starting to talk about a larger grow here, not your average closet grow.

 

Pepe being an A/C tradesman wondering if you could help. Ive bought a S&P TD-350/125 in line duct fan. The fan reckons it removes 360m/h max. My grow room is only 1m*1m*2m. I have got ventilation holes drilled at the bottom of the room and intend to connect the fan to the ducting already in place that was used by the gas boiler (gas now diconnected). The aluminium ducting goes through the wall venting outside. The ducting already there appears to be 100mm whilst the fan is 125mm. Will I be OK using some sort of reducer? Also with the fan removing so much air could it produce a constant negative pressure reducing the CO2 availale to the plants. Or will the fresh air enter the room faster to compensate the large extraction rate.
The intake vent consists of about 40 10mm holes drilled in a square plus gaps around incoming water pipes. Theres also a 75mm hole with a grill in it on another wall.
Basically I'm asking can you pull too much air out of a small room. Or as long as the temp and humidity are OK is it the more the better?

 

Reducing from a 120mm to a 100mm duct won't pose any problems.

The only problem would be as you said. You will be exchanging air faster, so if you use C02, you will have to adjust your C02 output to accomodate the larger flow.

Negative pressure will not cause a problem. In fact it will help to keep the smell going out the exhaust rather than permeating back into your house.
In reality, you must have negative pressure in your grow, or else your intake will be acting as an exhaust.

Too much negative pressure might strain your exhuast fans though. You'll know, if the door to your grow room has suction, then there is a good chance that you have too much negative pressure
If that's the case, then just make your intake larger.

 

Buffoonman, sup dude!
I grow in a sealed set-up, that means I exaust no air from my grow and no air from outside comes into my grow so I am not too sure about actively vented grows like yours but I know they recommend venting the total volume of your grow room every 5 minutes. In other words you would need to pull out around 24m/h. Your fan is rated at 360m/h so it's way too powerful for your set-up.
Here's what I suggest you do: go to a hardware store and get yourself a fan speed controller, don't get a light dimmer, that will fuck up your fan motor. Make sure it's a fan speed controller. They are around 10-15$ here in Canada. This controller will allow you to tune your fan and slow it down a bit.

You didn't say if you have your fan hooked up to your hood or not and I don't know what kind of light power you are running either. So you might need to pull out more than the standard room size every 5 minutes just to keep your heat down, I don't know. In this case, you can raise or lower your fan speed at will.

I don't think you can pull out too much air but it can become overkill and unnecessairy. In your case, you'll be throwing out too much of your house's air for nothing and this will show on your heating/cooling bill so you have to reduce that fan's speed.

I assume you are not using any CO2 system so pulling too much air is not going to reduce your CO2 availability, it's only going to me a problem is you don't pull out enuf air but this is not your problem here.

As Nickelbag said, using a 125mm fan on a 100mm duct is going to put some strain on your fan but only if you have it on full blast. The fan would be trying to such a large amount of air while the duct is only giving it a little bit. It's not only putting strain on the fan's motor but it's also noisier. But again, your fan won't be running full blast so it's not an issue in your case.

I don't think you can pull TOO MUCH air as to become a problem for your plants. I just think it's just way more than what you need, kind of like using a fire extinguisher to blow out a candle, it does the work, but it's not a need to use a fire extinguisher.

Get a fan speed controller and you'll be fine. That way, you can determine what speed suits your heat requirements and your noise levels.

I hope this was helpfull, let me know if you need more.

Cheers, PepeLapiu

 

Thanks for the advice. I am using a 400W HPS light. With the room only being 1m*1m*2m didn't think I would get away with a bigger one. The temp at present is 75 this is without the new extractor fan ( at present I have two small expelair fans going.)During the dark period I switch one off. Leaving the smaller of the two going just to keep humidity and smell down a little. The temp drops to 61 during there night cycle. Fans are in the wall not connected to the hood. ( I have an oscillating fan blowing over the top of the plants to do the cooling job.)
Drifted off there. Back to the new in line fan, it looks more like a jet engine glad I didn't get the 250mm one. It is two speed depending on how you wire it. So I will wire it to the lower speed and see how that goes. Eventually I will connect a carbon scrubber to it. ( Does it matter what side of the fan the scrubber goes?) As the fan will be connected to a reducer it will only be able to go on the inside. Is this OK. I have no CO2 added just relying on fresh air. Now you have told me you can not extract to much air I suppose as long as the temp is OK the more the better within reason.
Next grow will use a 600W light. As this is the first grow in my new place Its more about tweaking things and learning what the room needs. Don't normally use soil, but to be honest I like the simplicity of it and I havn't notice much of a difference in plant growth. If you need three or four extra days in veg it seems a good trade off for all that mixing and testing. Saying that though obviously havn't seen the final product yet, but I tell there won't be a big difference. Used to use lots of added CO2. But with just the oscillating fan blowing on the plants it seems to be doing really well. But I always found the extra CO2 came into its own during flowering . Depends what you want. From my new room aiming at 10 ounces personal per crop. Won't get this of the first one as half will be male. But with cuttings and the 600W light next one should surpass this. Thanks again for the advice.

 

Blower fans (or squirrel cage fans) are usually better suited to blow into the scrubber while inline fans usually do better at pulling the air from the scrubber. Additionnally, the scrubber I have comes with a cloth on the outside to filter out larger particules like dust and bugs so it doesn't obstruct and clog up the carbon so with mine, I would rather pull the air out of the filter. However, a co-worker of mine disagrees, he thinks all fans do a better job at pushing, he said pulling damages the motor. I think you can do either without any problems.

Good luck with the grow dude!

 

Cheers I will be pulling the same as you. Have no choice. The inline fan I have is of a high quality designed to run 24/7 so hopefully there should be no problems with the motor especially as it will only be running at half speed. Havn't purchased a carbon scrubber yet. With the two small fans running and the door shut no smell is escaping whatsoever at the present time, opening the door is a different matter the whole house smells but it rapidly vanishes once the door is closed. I read a growers report saying that ICE seemed to smell more in veg than flowering. I won't be counting on that though and buying a scrubber in a couple of weeks.
During my last grow I had three ionisers on the go these seemed to cope with the smell quit well. The room was three times the size so this grow I thought I'll get away with one, but it dosn't seem to be making any difference. Have you had any experience with air ionisers?

 

Buy the biggest scrubber you can afford, the bigger the better.
And no, I have never used anything other than scrubbers. What's your take on ionisers?
I think if I was exausting to the outside, I would go with an ozonator.

 

I'm exhausting outside but on the second flloor at the back of the house i'm sure the smell disperses long before it can be detected. Ionisers are OK as long as you have a few on the go. For any seriously smelly varieties I expect they would be useless unless used in conjunction with something else. Certainly would not rely on them as a sole means of odour reduction. I have never tried an ozone generator but from the reports I have read they do a lot better job than an ioniser. I may buy one but keep it a good distance from the plants. Read somewhere that the ultra violet ones are better but I could not comment on this.

 

The thing is, ozone can be dangerous for humans so if I was to use it, I would use it in my exhaust. I wouldn't control he smell inside the grow but it would prevent the exhast smell.

 

Do you reckon certain seeds can be more likely to turn male? Ive read read many reports claiming high percentages of male plants from Nirvanas seed strains. I always thought it depended on how they were grown and basically pure chance that generally worked out around 50/50. But from my 10 Nirvana seeds I seem to have a 70 or 80 percent male ratio confirming the reports I have read. I know this is a bit off the subject but as your the master grower thought I would ask.