Fans/controllers: variable fan / thermostat: worth it?

Hi I am setting up my first grow tent 2x4' specifically the fans. I want this to be quiet (i just hate noise I'm not trying to make it covert though), and it leads me to a few questions.

I don't want to be farting around with fan speeds almost ever...seems silly for something so easily automatable. But I'm worried I'm over thinking something simple

So 3 questions:

1. Are adjustable fans worth it? I figure I just buy a quiet one and call it a day. Looking at this one right now becuase someone is selling one for 40$
2. Do any thermostats adjust fan speed or are they all just on/off like a home thermostat?
3. Also do I need a thermostat? It seems like a dialed in temp/RH would be mandatory but I don't know anything.

This thing is awesome.

Look into duct mufflers

Temperature is controlled by the room the tent is in not the fan, the fan just cycles air at a set cfm per tent size. I prefer a variac over automated and one speed does do all quite well.

A friend uses automated fans, his complaint was you can here them changing speeds more than the quiet hum of them at a constant speed.

chico1st said:

Hi I am setting up my first grow tent 2x4' specifically the fans. I want this to be quiet (i just hate noise I'm not trying to make it covert though), and it leads me to a few questions.

I don't want to be farting around with fan speeds almost ever...seems silly for something so easily automatable. But I'm worried I'm over thinking something simple

So 3 questions:

1. Are adjustable fans worth it? I figure I just buy a quiet one and call it a day. Looking at this one right now becuase someone is selling one for 40$
2. Do any thermostats adjust fan speed or are they all just on/off like a home thermostat?
3. Also do I need a thermostat? It seems like a dialed in temp/RH would be mandatory but I don't know anything.

Click to expand...

if you need quiet id recommend an AC infinity. or using oversized fan/filter and running it low with variable speed controller. a 6" fan running at 20% will be a lot quieter than a 4" at 50%

I use one of these

Bought it local though on ebay.uk , quietest fan on the market as far as I know, but it isn't as fancy as the AC infinity
I use an additional speed controller with it which you wouldn't need with the AC infinity.

You have to pay attention to the CFM though, because it doesn't shift as much air as your average 4" or 6" fan.

AC infinity would the simpler option

2Hearts said:

Temperature is controlled by the room the tent is in not the fan, the fan just cycles air at a set cfm per tent size. I prefer a variac over automated and one speed does do all quite well.

A friend uses automated fans, his complaint was you can here them changing speeds more than the quiet hum of them at a constant speed.

Click to expand...

oh wow this is blowing my mind. People don't set a thermostat on the tent? You set your whole house to 75F and just pull the air for smell reduction? My thermostat is on a different floor so I can't imagine it would keep things very fixed near my tent, but I can test it.

What about RH then? You just use the whole house RH control as well except when drying? I'm in Canada so the house RH in the winter is pretty low even with a humidifier (due to window dew point).

View your tent as a box that sucks air through quite fast, its not in the tent long enough to heat up or change humidity.

Whatever it sucks in will be the inside temp and humidity so the room the tent is in is what you control and not the tent.

Dont put your meters in the light if your trying to read just the air temperature and humidity.

Low humidity is good no problems to a hash plant.

chico1st said:

oh wow this is blowing my mind. People don't set a thermostat on the tent? You set your whole house to 75F and just pull the air for smell reduction? My thermostat is on a different floor so I can't imagine it would keep things very fixed near my tent, but I can test it.

What about RH then? You just use the whole house RH control as well except when drying? I'm in Canada so the house RH in the winter is pretty low even with a humidifier (due to window dew point).

Click to expand...

For a small tent you could try a cheap 6" duct fan from Home Depot. They're way quieter than an inline fan.

chico1st said:

oh wow this is blowing my mind. People don't set a thermostat on the tent? You set your whole house to 75F and just pull the air for smell reduction? My thermostat is on a different floor so I can't imagine it would keep things very fixed near my tent, but I can test it.

What about RH then? You just use the whole house RH control as well except when drying? I'm in Canada so the house RH in the winter is pretty low even with a humidifier (due to window dew point).

Click to expand...

Low humidity isnt an issue. Plants grow fine at 20% once they get past that first week of seedling stage. High humidity is the only big concern. If you keep your house at 70 degrees, with the light on in your tent and fan on a low speed, the light will warm the tent up a bit. So lights on is say 78 degrees, lights off is 70. A lot if it is learning how your exact setup will worth with the room and hose you are growing in. If you want super quiet, get a 6'' ac infinity fan and run it at 25%. It will be basically silent and move enough air to cool a 315w cmh light.

AC infinity is the way to go. Quiet, has a built in therm and adjust speed based on desired temp. Haven’t found anything to beat it. I had a manual speed controller before, won’t buy that again.

Dontjudgeme said:

AC infinity is the way to go. Quiet, has a built in therm and adjust speed based on desired temp. Haven’t found anything to beat it. I had a manual speed controller before, won’t buy that again.

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I have AC infinity with the manual controllers and they are fine. For my veg tent i have the automatic controller because i want to keep a perfect 79 degrees at all times but for the flower tent i need a good amount of air moving at all times anyway so the manual is fine for that because i just set it to 50% and forget it- when the 1000w is on, temp stays at 78. When its off, it drops to the temp of the lung room. Because the lung room temp changes when the flowering light is running, i need the veg tent to be able to automatically control itself.

JoeBlow5823 said:

I have AC infinity with the manual controllers and they are fine. For my veg tent i have the automatic controller because i want to keep a perfect 79 degrees at all times but for the flower tent i need a good amount of air moving at all times anyway so the manual is fine for that because i just set it to 50% and forget it- when the 1000w is on, temp stays at 78. When its off, it drops to the temp of the lung room. Because the lung room temp changes when the flowering light is running, i need the veg tent to be able to automatically control itself.

Click to expand...

No argument with that method. I just try to be as non-hands on as possible. Sometimes my flower tent warms up too much because it’s in my room. I’ll be freezing because my central air is on, but the ladies are loving it. So I have to go adjust the fan speed to accommodate my skinny bones. That’s where the auto controller came in handy. But I’m not knocking your method at all.

Dontjudgeme said:

No argument with that method. I just try to be as non-hands on as possible. Sometimes my flower tent warms up too much because it’s in my room. I’ll be freezing because my central air is on, but the ladies are loving it. So I have to go adjust the fan speed to accommodate my skinny bones. That’s where the auto controller came in handy. But I’m not knocking your method at all.

Click to expand...

Yeah there are a lot of factors. To run a 5x5 and 3x3, i use my entire house as the lung room. Grow room dumps air into the basement and it basically has to travel through the entire house to get back into the grow room so the way things are setup for me just running the fans at a medium speed (still pretty quiet) all the time is perfect. I even have two oscillating fans running on low 24/7 in the basement and a dehumidifier so the air is always dry and moving to prevent any mold issues. And then the furnace/central air keeps the house at 67-70 degrees all the time. Ive put far to much time into fine tuning my setup lol but now that i have, it runs incredibly smoothly.

I like my T6, having an automatic setting to run the fan if either temp OR humidity exceeds a set point makes keeping the environment in the room more stable.
Compared to my old 6" centrifugal, it is a lot quieter.

Dontjudgeme said:

No argument with that method. I just try to be as non-hands on as possible. Sometimes my flower tent warms up too much because it’s in my room. I’ll be freezing because my central air is on, but the ladies are loving it. So I have to go adjust the fan speed to accommodate my skinny bones. That’s where the auto controller came in handy. But I’m not knocking your method at all.

Click to expand...

I like the hands off-ness of how that but with the AC T6 how do you deal with setting day and night temps seperately as people like to do?

2Hearts said:

View your tent as a box that sucks air through quite fast, its not in the tent long enough to heat up or change humidity.
Whatever it sucks in will be the inside temp and humidity so the room the tent is in is what you control and not the tent.

Click to expand...

I discovered about lung rooms today. That's nuts!
Do people seperately heat/cool the room the tents are in from the rest of the house? or usually just run the whole house as the thermostat?

What about if you have CO2. Is that in the tent specifically? It gets dangerous and I wouldn't want to live in a house with even slightly elevated co2

Edit: this room design stuff gets super complicated!!

My room runs during the night and is sleeping during the day.
I only run during the winter because I don't have a/c in the house.
My T6 will cycle the fan at night as the room temp exceeds the set point.
During the day when the girls are asleep, the fan will run if the RH exceeds the set point.
Doing it this way keeps the temps within a 10 deg swing and RH will stay within 5% of where I want it.
CO2 requires a sealed room to be effective.

chico1st said:

I like the hands off-ness of how that but with the AC T6 how do you deal with setting day and night temps seperately as people like to do?


I discovered about lung rooms today. That's nuts!
Do people seperately heat/cool the room the tents are in from the rest of the house? or usually just run the whole house as the thermostat?

What about if you have CO2. Is that in the tent specifically? It gets dangerous and I wouldn't want to live in a house with even slightly elevated co2

Edit: this room design stuff gets super complicated!!

Click to expand...

It all depends on your setup. Small lights you can typically just use the environment of the room a tent is in for the purpose of a lung room. But the typical bedroom does not get enough AC from central air to cool a 1000w hps light. And if its 70 degrees outside, your ac probably isnt running at all. CO2 isnt really dangerous. You breathe it out with every breath. CO or carbon monoxide is whats dangerous. Everything really depends on your specific setup there are so many variables. Any hobby size grow really doesnt need supplemental CO2. Just what you your family and your pets breathe out is enough. One thing i love about growing- it keeps the air super fresh when the house is sealed up all winter.

JoeBlow5823 said:

Low humidity isnt an issue. Plants grow fine at 20% once they get past that first week of seedling stage. High humidity is the only big concern. If you keep your house at 70 degrees, with the light on in your tent and fan on a low speed, the light will warm the tent up a bit. So lights on is say 78 degrees, lights off is 70. A lot if it is learning how your exact setup will worth with the room and hose you are growing in. If you want super quiet, get a 6'' ac infinity fan and run it at 25%. It will be basically silent and move enough air to cool a 315w cmh light.

Click to expand...

Perfect

chico1st said:

I like the hands off-ness of how that but with the AC T6 how do you deal with setting day and night temps seperately as people like to do?


I discovered about lung rooms today. That's nuts!
Do people seperately heat/cool the room the tents are in from the rest of the house? or usually just run the whole house as the thermostat?

What about if you have CO2. Is that in the tent specifically? It gets dangerous and I wouldn't want to live in a house with even slightly elevated co2

Edit: this room design stuff gets super complicated!!

Click to expand...

My entire house is pretty much my grow room, if you look at it from an environment stand point, because I exhaust in the same room my tent is in. So my AC running is necessary to combat heat. But as far as cO2 in concerned, I don’t use it. Reason being, my tent isn’t sealed, so having cO2 in there is just a waste as well as dangerous because my exhaust would just suck it out anyway. I’ve ran closed rooms before, and yes, cO2 helps tremendously with the plant putting on weight, but I don’t have that luxury now.