Grill Direction - HVAC - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC


Thread Tools Display Modes
Old 11-03-2011, 06:44 PM   #1
Join Date: Oct 2009
Location: Indiana, PA
Posts: 1,371
Rewards Points: 640

Grill direction

Does it matter what direction a return air grill faces? our furnace is in the basement and all the return air grills when we bought the house had the open end facing towards the ceiling (they are all on the lowest part of the floor) if the duct is going down, and the louvers point down does that impact the air flow? should they pull the air in one direction instead of making the air do a U shape to go from the floor up then pulled back down into the duct? or does it not matter at all? I've noticed since the last HVAC guy was here and flipped all them around we have a lot more humming in the duct system....


BlueBSH is offline   Reply With Quote
Old 11-03-2011, 07:26 PM   #2
biggles's Avatar
Join Date: Jan 2008
Location: Long Island
Posts: 3,630
Rewards Points: 2,000

its more for looks then the air moving thru them having them pointing down at a low point on th wall blocks the view into the duct...unit will not be effected you usually don't want any noise thru them...


biggles is offline   Reply With Quote
Old 11-03-2011, 08:19 PM   #3
Join Date: Aug 2011
Posts: 729
Rewards Points: 500

Check to make sure the grills are screwed in tight. You can push on the louvers to see which one is humming.

But I have a question that may or may not relate to this,
Do you have hearing aids? I ask because I used to take care of a retirement community. It seemed that those that had hearing aids had the most complaints with system noises.
Master of Cold is offline   Reply With Quote
Old 11-04-2011, 01:10 AM   #4
Join Date: Jul 2011
Posts: 615
Rewards Points: 500

Humming is the result of the grille blades vibrating as the air is pulled through them.It doesn't make much differance which way they are facing so if turning them around stops the humming then do that.
The only other way to stop the humming is to increase the size of the return grilles or the return ducts ,probably both.
If you do a tempature rise check and the temp is too high you can be sure you need better duct or more grilles.At that pouint I would question if you have enough comfort getting into the house as if they cheaped out on the return,they probably cheaped out on the supply too.
REP is offline   Reply With Quote
Old 11-04-2011, 05:14 PM   #5
Join Date: Feb 2011
Location: Vancouver BC
Posts: 1,748
Rewards Points: 1,012

If turning them back the way they were doesn't sort out the harmonic vibration then you can often reduce or eliminate most of the noice by altering the direction of every 2nd grill fin by 10 degrees with needle nose plyers.
A thin bungee line that is attached from deeper inside of the duct to hook onto the back of the center of the grill will considerably dampen the grills vibrations. But...

Replacing it with a coarse wooden return air grill is the surest bet for eliminating that type of noice.
how is online now   Reply With Quote
Old 11-04-2011, 08:10 PM   #6
30 year tech
hvac122's Avatar
Join Date: Dec 2007
Location: Lincoln, Nebraska
Posts: 427
Rewards Points: 250

Have you changed your filter recently. Usually the noise is a lack of return air as said. Most of the time a wooden grille will block the return even more.
Would it be possible to add more return airs if needed?
hvac122 is offline   Reply With Quote
Old 11-04-2011, 08:18 PM   #7
Join Date: Aug 2011
Posts: 729
Rewards Points: 500

The cheap stamped return grills are notorious for vibration.
The alternative is a louvered return grill.

Here is a recommended example


Master of Cold is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to clean stainless steel grill?? JohnnyD44 Appliances 2 07-21-2011 08:32 AM
Help with Nat. Gas Line for Grill albertgarrido Plumbing 7 06-29-2010 01:57 PM
Which direction to install laminate flooring - Floorplan attached oONightFireOo Flooring 8 01-31-2010 03:01 PM
Painting A/C Fan Grill fritzycat1 Painting 3 09-09-2009 04:50 PM
Carpet on Stairs, Hallway: Nap Direction Carol Emmarie Flooring 5 03-26-2009 11:40 AM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1