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

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-18-2010, 10:18 AM   #1
Newbie
 
Join Date: Apr 2010
Posts: 5
Share |
Default

Central AC Return


We have a small 2 story house (1550s.f.). The air handler/heating unit is located in the garage mounted on a enclosed box. The filter is located on the bottom of the air handler and the return grill is mounted on the wall in the family room. The return runs under a staircase through the wall to the box. The garage side of this void is not insulated and as best as I can tell the staircase void does not appear to be sealed (conditioned space) My question/problem.

#1 I want to fabricate a insulated pathway/duct from the return grill to the air handler to improve the systems efficency (conditioned to unconditioned space).

#2 And add a return duct from the second story ceiling back to the pathway/duct.

Do I have to reduce the existing returns size in direct proportaion to the new returns size? And can the new return duct be connected to the existing (improved/insulated) return anywhere to create the vacumun effect required?

I'm pretty handy but I don't spell to well .
Any and all input is appreciated.

jwwilliams is offline   Reply With Quote
Old 05-18-2010, 12:54 PM   #2
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,538
Default

Central AC Return


Weather you need to reduce or not, depends on how big the duct to the second floor is. And how big it is to the current grille.

A drawing of what you have now. And what you want to do would help.

beenthere is online now   Reply With Quote
Old 05-18-2010, 08:59 PM   #3
Newbie
 
Join Date: Apr 2010
Posts: 5
Default

Central AC Return


Thanks Beenthere, I'll draw it up as best I can.
jwwilliams is offline   Reply With Quote
Old 05-25-2010, 07:23 PM   #4
Newbie
 
Join Date: Apr 2010
Posts: 5
Default

Central AC Return


Attached is a before and after drawing. The AC is a 3.5 ton unit, the air return grill's outside dimensions (31.5 x 11.5), proposed upstairs duct run I hope will be 8", the built up main return duct will be made out of insulated foam board rated at R6 minimum.

Any and all help is appreciated.
Attached Thumbnails
Central AC Return-dscn2681_edited.jpg   Central AC Return-dscn2682_edited.jpg  
jwwilliams is offline   Reply With Quote
Old 05-25-2010, 07:29 PM   #5
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,538
Default

Central AC Return


If your current return is slightly restricted/undersized. Then you don't need to make a reduction in the trunk anywhere.

If its not, just put a small restrictor plate just after where you attach your new return duct to. It will cause air to be pulled from the second floor return.
beenthere is online now   Reply With Quote
Old 05-25-2010, 10:49 PM   #6
Newbie
 
Join Date: Apr 2010
Posts: 5
Default

Central AC Return


Sorry, do you mean restrict the opening at the existing (main) air inlet (if over sized) to cause air to be sucked from the add on duct run?
jwwilliams is offline   Reply With Quote
Old 05-26-2010, 04:48 AM   #7
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,538
Default

Central AC Return


If the area where your going to tap the new return duct into. Won't be easily accessible later. You can restrict it at the grille.

beenthere is online now   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Should I have let the ac guy close off a return? windowman3 HVAC 4 09-13-2009 08:23 AM
return air honola HVAC 11 08-13-2009 07:41 AM
Enough Return Air? mjbxx HVAC 3 02-12-2009 06:26 PM
Central Air Installation Question ??? WorkOnIt HVAC 3 03-07-2008 04:04 PM
Central Air return duct location backpacker2 HVAC 3 05-28-2007 10:07 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.