Exhaust Fan Somewhat Loud

Hey everyone!

I have a 6" exhaust fan that is a little louder than I’d like. I have the silencer on it which helped a lot! Now I’m down to just motor noise pretty much. Do you know if I can insulate this motor? It’s significantly quieter with a blanket wrapped around it. Not sure about it overheating. I would think the airflow cools the motor. I’m wondering if anyone has insulated theirs. So far it seems cool still but I’ll keep checking.


You can insulate the housing. The motor is cooled from the constant air flow while it’s running. I would use something a little more flame retardant than a blanket in cause of an electrical short. Better safe than sorry. :slight_smile:

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Thank you. Moved it inside the tent. Helped a bit more. I’m not worried about heat since it’s in a cool basement. I’ll get some proper wrap for it.

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I put mine outside on the roof, helped the noise a little and it keeps the heat out of the tent …I would imagine, I didn’t have it inside

I’m going to slow the fan down a little more with a dial thing my buddy has. It’s pulling a ton of air through the tent. More than it needs I think. The tent is bowing in and tight even with the bottom vents all the way open. It’s going to implode but you can tell there is a ton of suction going on.

And it’s not super bad. With everything in the house turned off I can hear it below the living room. Just don’t want anyone asking questions. Probably never would but…

This is how I have it now. Silencer is sticking out the side.

I’m not familiar with a silencer but you definitely need a speed control, I hardly ever run at 440 usually its way down on the lower end (but it’s kinda loud even then)

It has a dial but it barely makes a difference between high and low. The gadget my buddy has will slow it down more. The silencer just breaks up the air coming out, which was the loudest part before I put it on.

I have a Hydrofarm speed controller, it slows the 440 down to almost nothing, way down below my 220 inlet, I have to turn it up about half way if the 220 inlet is running

Found the device. It’s a Variac Variable Transformer. I see reviews on Amazon from growers saying it works perfectly to fine tune fans and doesn’t make the motor hum at all. I’ll try one tomorrow and see how it works.


Don’t know what that is but I paid less than twenty bucks for an Active Air speed control, it works well


Edit: I was reading about that thing at your link and there’s so many warnings! I don’t even know what that is but that sounds more like lab equipment not something you’re going to stick in your grow tent? …I’m just saying

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It’s basically the same thing I would guess. He has it already so I’ll try it. If not I’ll get what you linked. And, no. It won’t be in the tent :slight_smile:

Some people wire a standard dimmer switch in line, there basically just a potometer

I’m thinking about getting this for my exhaust fan. Works like a light dimmer switch.

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Nice. Going to try the variac tomorrow. I’ll report back how it works. Obviously, it’s more money but since I already have it available I’ll give it a go. My second Viparspecta 900 will be here tomorrow :relaxed:. Then I’ll really be able to see temps at lower fan speed. Highest it’s been so far is 72. Would like it a bit higher.

@Mathew420 , @paranorman is correct as to the controller you need ,follow his link. they can be had for 20.00 US or less on Amazon .I use a 6’ blower like you posted and it came with the speed controller like the one he posted , youll find in MR.P’s link … :wink: good growing .
Hammer .


@Matthew420 .See the above link .

In researching more it looks like the variac is a great way to go, aside from their cost and size. I have one available at no cost and plenty of space. Now I’m anxious to try it. I’ll post some feedback once connected.

Ok, the variac works amazingly well. Super fine tuning of fan speed. I can also see voltage and amperage draw, as well as line-in voltage. Maybe a bit much if you’re on a budget but my buddy had it already.

Rating: 2 Buds Up :+1::+1: in my opinion.

I got this…cheap as n works a treat.

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