Exhaust fan help

[masho95]

I purchased a cheap amazon kit and got what I paid for I think lol. Here's my issue, my tent is a basement setup and the exhaust to outside the house is going through about 10-15ft of duct. The fan is a 4" Intertek inline continuous duty fan. Rated at 189 CFM. The tent is 32"x32"x63". By the time the exhaust gets to the exit of the house it feels like there is almost no pressure. The exhaust isn't even enough to open the flaps on the exhaust cover.

Is this a matter of just not enough fan? Can I have 2 fans in the run? Thanks for any ideas!

 

[masho95]

Well I moved the tent and whole setup to the other side of the basement closer to the exhaust exit. After getting the inline fan mounted and ducted to the outside it had fantastic suction! Attaching the carbon filter from the kit (used for 4 months this way) provided no exhaust. Seems like air isn't being properly pulled through the filter. Ordered a new one on Amazon and will find out Monday if all is well with a new one.

 

[Notthecops]

Stick with Vortex brand fans IMO. They last and are worth every penny. cheaper ones aren’t always moving the amount of air they are rated for.

With a run of 15 feet, and a small 4inch fan, it could take a few minutes for the pressure to build in the exhaust hose.

However, if your exhaust lines are air tight, the issue is the fan.

 

[FastFreddi]

A good rule of thumb...think you need a 4in? Get 6...need a 6...get an 8.
Paired up with a fan speed controller, you can reduce speed increasing efficiency.
FF

 

[Notthecops]

A good rule of thumb...think you need a 4in? Get 6...need a 6...get an 8.
Paired up with a fan speed controller, you can reduce speed increasing efficiency.
FF

Agreed 100%. A fan controller is a must also when buying bigger.

 

[masho95]

I'm not concerned with energy efficiency. Is there any grow increase with a more efficient fan?

 

[FastFreddi]

Well, the more air that is exchanged, the more co2 your plants will get, and as long as it is filtered somehow, the less chance of nasties like pm or Botrytis taking hold.
FF

 

[masho95]

Well, the more air that is exchanged, the more co2 your plants will get, and as long as it is filtered somehow, the less chance of nasties like pm or Botrytis taking hold.
FF

Stupid question. What is PM. I've seen it over and over in threads and best guess was Pest&Mold. Intake should be filtered? Right now I just reset the tent and changed the setup. Going to be carbon filter inside the tent. Inline filter is mounted outside the tent and then vents outside. The new run about 5 ft of ducting now. I have a 4 inch duct running to the outside of the tent and a fan blows air towards that.
I apologize if any of these questions sound stupid. I'm new and learning! Thank you!

 

[FastFreddi]

Stupid question. What is PM. I've seen it over and over in threads and best guess was Pest&Mold. Intake should be filtered? Right now I just reset the tent and changed the setup. Going to be carbon filter inside the tent. Inline filter is mounted outside the tent and then vents outside. The new run about 5 ft of ducting now. I have a 4 inch duct running to the outside of the tent and a fan blows air towards that.
I apologize if any of these questions sound stupid. I'm new and learning! Thank you!

Powdery mildew( knock wood) the bane of indoor growing.

 

[masho95]

Well, the more air that is exchanged, the more co2 your plants will get, and as long as it is filtered somehow

So should I have intake air filtered too?

 

[coreywebster]

Attaching the carbon filter from the kit (used for 4 months this way) provided no exhaust. Seems like air isn't being properly pulled through the filter. Ordered a new one on Amazon and will find out Monday if all is well with a new one.

A new what, fan or filter?

 

[masho95]

A new what, fan or filter?

Ordered a new filter. When the old one is attached no air is exiting the exhaust port outside the house. Without the filter attached it's blowing like a jet engine.

Now without a filter I can't get my temps and RH to stay high enough. The 189 CFM fan while constantly running is exhausting the air out of the tent before it can get to high enough temps and humidity.

With the fan running max temp got to 68 degree and 30%. That's with a heater blowing directly into one of the flaps at the bottom and a humidifier inside the tent and one outside near the air intake.

Looks like I'm going to have to get a new controllable fan. With a small 32 inch square tent I don't think it needs anywhere close to all the fan power.

Edit: New tent location has me struggling to get temp high enough even without the exhaust fan running. 73.5 is about as high as it wants to go. Just ordered a controllable fan and it'll be here Monday with the new filter. Going to work on the heat issue today. Gahhhh...

 

[coreywebster]

Ordered a new filter. When the old one is attached no air is exiting the exhaust port outside the house. Without the filter attached it's blowing like a jet engine.

Now without a filter I can't get my temps and RH to stay high enough. The 189 CFM fan while constantly running is exhausting the air out of the tent before it can get to high enough temps and humidity.

With the fan running max temp got to 68 degree and 30%. That's with a heater blowing directly into one of the flaps at the bottom and a humidifier inside the tent and one outside near the air intake.

Looks like I'm going to have to get a new controllable fan. With a small 32 inch square tent I don't think it needs anywhere close to all the fan power.

Edit: New tent location has me struggling to get temp high enough even without the exhaust fan running. 73.5 is about as high as it wants to go. Just ordered a controllable fan and it'll be here Monday with the new filter. Going to work on the heat issue today. Gahhhh...

Its the fan that the problem if it cant overcome the resistance of the filter.
Unless the filter had plastic wrap under the dust cover.

I tried googling your brand of fan when you first posted to check if it was up to the job, but I couldn't find anything on it.

Can you link it so we can check it out.

Are you sure there was no airflow or was it just so low you could hardly feel it? Mine don't blow a gale at the exit point but they still do the job and I still have to use a fan speed controller.

 

[coreywebster]

What light do you have in there?

 

[masho95]

Its the fan that the problem if it cant overcome the resistance of the filter.
Unless the filter had plastic wrap under the dust cover.

I tried googling your brand of fan when you first posted to check if it was up to the job, but I couldn't find anything on it.

Can you link it so we can check it out.

Are you sure there was no airflow or was it just so low you could hardly feel it? Mine don't blow a gale at the exit point but they still do the job and I still have to use a fan speed controller.

It was the fan and filter included in this kit.
Inline Duct Fan: 120V60HZ; 101Watt; 0.86A; 2850RPM; 189CFM; wired with junction box, strain relief and power cord, Fluted on both ends to receive ducting

This is my light.

The airflow with the carbon filter attached is so low it won't even push open the flaps on the vent at the outside of the house. I removed the outer pre-filter and there was nothing under it, just the hole openings to the inside of the charcoal medium part. Just a tiny bit of dust from 4 months of use, nothing crazy at all. I've pretty much replaced everything in the kit but the tent now. Knowing what I know now I definitely wouldn't have done a cheap kit. Oh well, now I know I really enjoy growing and can move forward.

But I just picked up this new fan and filter. I'm sure this combo should remedy the exhaust issue. The AC Infinity ducting is amazing if you haven't checked it out also. Struggle free attaching and cutting it to length.