any way to make fans quieter?

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danskman

New Member
Jan 3, 2018
2
Wisconsin
We replaced our very old jci with a vogelzang norseman 2500 a few months ago. Although its much quieter then the old jci its still loud enough that we need to crank the tv everytime it kicks on.

The furnace is centrally located in our house. And we dont have a basement. We have chose to not locate it outside either since we are having consistant temps of -10° to -25° in northern wisconsin. Im not willing to bundle up and stoke the furnace every 4 hours out there.

So the question is there any way to quiet down the blowers? There is ductwork going to each room but no cold air return. Its just a box on the back of the furnace with a filter in it.

Maybe sound deadner? Im not just yet willing to relocate the fans to a remote location.
 
If I'm picturing your setup correctly you have two fans mounted low on the rear of this furnace? I suppose you could buy some fire-rated board and try to box-in those fans a bit. Due to the requirement for clearance on the back side you shouldn't use something not properly rated to build the box.

Enclosing the fans could also create a heat issue for the fans themselves though. I guess I'd first try to build some kind of metal enclosure that only encloses three sides? See if that helps?
 
Is it the rush of air or the fan motor itself? You could reduce the speed.
 
There is a shroud around the fans now. Previous owner used the furnace as supplementary to his propane furnace so it was plumbed into his existing ductwork. He left the small portion of the cold air return when i bought it. I still use it aince it makes a good filter holder.
As for the fans. There is 2 small "squirrel cage" style fans. 550cfm each so yeah they do spin pretty quick. I worked maintenance as electromech for many years. I already know the only way im going to slow them down is by changing the motors for lower rpms or using a frequency drive to power them. Some can be variable by resistance like older stuff but these are fixed resistance motors and fixed rpm.
 

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Oh fans! Why was I thinking squirrel cage blowers? If the noise they make just spinning won't get you, installing them in a box or duct will!

Find a way to change them to squirrel cage blowers but be careful, not all blowers are equal. Some of those offered by Grainger can be just as loud. Panasonic has come a long way with their exhaust fans on the noise output but I doubt they offer the blowers separately. You could find one of their units and pull the blower out. They list the decibel level of each of their units on line.