exhaust fans

[eds]

I made a mistake and installed some broan QT80 exhaust fans per the designer's suggestion and now I can hear them across town. These fans have a rating of 1 sone, I have swapped motors and gone to a QTRE 80 and a QTXRE 80 these carry a sones rating of .8 and .3 respectivly. This has made a slight differance but not enough to make me happy, does the length of exhaust, type of exhaust pipe, and size come into play with the sones rating.

 

[Buck Parrish]

I made a mistake and installed some broan QT80 exhaust fans per the designer's suggestion and now I can hear them across town. These fans have a rating of 1 sone, I have swapped motors and gone to a QTRE 80 and a QTXRE 80 these carry a sones rating of .8 and .3 respectivly. This has made a slight differance but not enough to make me happy, does the length of exhaust, type of exhaust pipe, and size come into play with the sones rating.

I don't know the answer about the lenth of duct. But it seems reasonable that it might make some difference. But not enough to matter much.
If I want quiet. The panasonic whisper is the way to go.
Can you swap them out?

 

[tonyou812]

the less resistance the air flow has the better the sound quality will be. But im just curious .8 ? thats better than some of the best modles out there. Do you mean 8 sones perhaps, because that will sound really loud. I always prefer to use panasonic fans. I never have a problem with them.
Sometimes HVAC guys or who ever vents it will put a screw in to hold the duct in place and in doing so they manage to put it right were the "Flapper" is and keep it from opening when the fan is turned on. Or some modles have a piece of tape holding it in place for packing.

 

[eds]

I have used panosonic and will probably remodel them into this job, I just don't get how .8 sones can be this loud. I have 8 fans in this house and of the 5 that are running 4 will not pass the customers expectations or mine for that matter. My supplier will swap fans but I don't like the fact that the broan xtra quiet is as loud as the standard model.

 

[Palmbay]

Solid mounting and no vibration will get the fan as quiet as it can from the factory. I have used expandable foam around the fan housing in the attic space to quiet them down and it works well.

 

[satcom]

I made a mistake and installed some broan QT80 exhaust fans per the designer's suggestion and now I can hear them across town. These fans have a rating of 1 sone, I have swapped motors and gone to a QTRE 80 and a QTXRE 80 these carry a sones rating of .8 and .3 respectivly. This has made a slight differance but not enough to make me happy, does the length of exhaust, type of exhaust pipe, and size come into play with the sones rating.

Most of the manufactures claim the length and type, does make a difference, we just looked at a job where someone vented the exhaust into the attic, they are trying to sell the home and the inspection extimates are comming in above $20K for mold damage, just follow the manufactures instructions, so you don't run into any problems, use the length and type they approve..

 

[alfiesauce]

Sometimes HVAC guys or who ever vents it will put a screw in to hold the duct in place and in doing so they manage to put it right were the "Flapper" is and keep it from opening when the fan is turned on. Or some modles have a piece of tape holding it in place for packing.

I'd be checking this route as well.
We run into the screws issue way to often...
Or maybe a crushed vent?
Did a plumber put a pipe against the housing?
If it's a venting issue no matter how quiet of fan you get it will always be noisy.

 

[MASTERFRANK]

I made a mistake and installed some broan QT80 exhaust fans per the designer's suggestion and now I can hear them across town. These fans have a rating of 1 sone, I have swapped motors and gone to a QTRE 80 and a QTXRE 80 these carry a sones rating of .8 and .3 respectivly. This has made a slight differance but not enough to make me happy, does the length of exhaust, type of exhaust pipe, and size come into play with the sones rating.

Have supply house check with Broan about max duct run length and if hard piped the number of turns. I had this problem with a Nutone ( to many 90's in run )

 

[LLSolutions]

I know it doesn't help much now, but inline fans a re really coming down in price. In my home I used 1 inline fan for 2 bathrooms the cfm is still strong enough, and all you see is a 4" diffuser on the ceiling and you can't hear a thing.