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 07-26-2010, 06:48 PM   #1
Member
 
Join Date: Jul 2010
Posts: 82
Share |
Default

Duct Sizing and Replacement


I am thinking of running new duct work through my basement, one of the big reasons is because A) it is 46 years old B) I believe it sized wrong and C) I don't like the way it was run.

How do you figure the sizing of the main duct that all the runs link off of? Currently I believe the main duct is much to large, and if so it will give me more head room for my finished basement project. Is there a calculator for the amount of air moved?

DAdams982 is offline   Reply With Quote
Old 07-26-2010, 07:40 PM   #2
Member
 
Join Date: Oct 2009
Location: Nebraska
Posts: 2,362
Default

Duct Sizing and Replacement


What's the size of your AC? What size is the supply and return duct now?

Marty S. is offline   Reply With Quote
Old 07-26-2010, 07:45 PM   #3
Member
 
Join Date: Oct 2009
Location: Nebraska
Posts: 2,362
Default

Duct Sizing and Replacement


Soory for the lack of an answer. Yes there are duct calculators. Get one that also shows the equivalant feet of fittings.
Marty S. is offline   Reply With Quote
Old 07-26-2010, 07:45 PM   #4
Member
 
Join Date: Jul 2010
Posts: 82
Default

Duct Sizing and Replacement


Quote:
Originally Posted by Marty S. View Post
What's the size of your AC? What size is the supply and return duct now?
It is a 2.5 ton unit. It conditions a 1500sqft house. I will have to go measure the ducts tonight for you. The return is quite large with 3 large feeds to it, and the supply is huge, with 13 runs coming from it. All is uninsulated so when it reaches the opposite end of the house from the unit it is quite a bit difference in temp, so was looking at insulated flex duct.
DAdams982 is offline   Reply With Quote
Old 07-26-2010, 08:22 PM   #5
Member
 
Join Date: Jul 2010
Posts: 82
Default

Duct Sizing and Replacement


Actually.. what measurements should I take? Length of supply from furthest run from air handler? Height and width of supply? What should I measure to get the right measurements? Cause I found a calculator it asks for a few different things with acronyms I dont know.
DAdams982 is offline   Reply With Quote
Old 07-26-2010, 08:30 PM   #6
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,401
Default

Duct Sizing and Replacement


Are you trying to figure out if your current is big enough/too big. Or are you just going to replace it because its old.

For your current duct. Measure the size of all ducts from the air handler. To the furtherest supply. And a couple of the ones in between. And also do the same with the return.
beenthere is offline   Reply With Quote
Old 07-26-2010, 08:31 PM   #7
Member
 
Join Date: Jul 2010
Posts: 82
Default

Duct Sizing and Replacement


Quote:
Originally Posted by beenthere View Post
Are you trying to figure out if your current is big enough/too big. Or are you just going to replace it because its old.

For your current duct. Measure the size of all ducts from the air handler. To the furtherest supply. And a couple of the ones in between. And also do the same with the return.
First I am finding out if it too large. But replacing it because it is old and uninsulated is also a reason. I will measure as required.

DAdams982 is offline   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
How to size a replacement gas furnace B4Dark HVAC 10 06-10-2010 09:55 PM
100A Fuse Panel Replacement Charlie1101 Electrical 4 07-25-2009 02:22 PM
Sizing thoughts moneymgmt HVAC 3 10-28-2007 06:57 PM




Top of Page | View New Posts

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