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 10-07-2012, 12:22 PM   #1
Member
 
Join Date: Jul 2011
Location: Houston Texas
Posts: 1,061
Share |
Default

Confused about AC CFM on varying Furnaces


IS there not a standard number, say 400 cfm, per ton for furnace developement for use with AC, per ton?

I ask because I saw this one, but it indicates it is good up to a 5 ton Ac, but only produces 1800 CFM. Seems low for 5 tons to me?

http://www.alpinehomeair.com/viewpro...ctID=453065680

Comments, explanation?

digitalplumber is offline   Reply With Quote
Old 10-07-2012, 12:53 PM   #2
I'm Your Huckleberry
 
Join Date: Mar 2011
Posts: 5,620
Default

Confused about AC CFM on varying Furnaces


It'd be like a 5 ton blower on a lower speed setting. Since they don't make a 4.5 ton condenser (in half tons 3.5 is the biggest, then 4 and straight to 5) it's just a selling point that they say it is compatible and while it is it's not the best, correct match up.

You'll never get the full cooling parameters of a 5 ton system.

__________________
Thanks.
Doc Holliday is offline   Reply With Quote
Old 10-07-2012, 12:56 PM   #3
I'm Your Huckleberry
 
Join Date: Mar 2011
Posts: 5,620
Default

Confused about AC CFM on varying Furnaces


Now if used with a heat pump than 350 cfm per ton is the common number so 1750 cfm would be all that's required, that would work with a 5 ton heat pump.
__________________
Thanks.
Doc Holliday is offline   Reply With Quote
Old 10-07-2012, 05:37 PM   #4
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,778
Default

Confused about AC CFM on varying Furnaces


400CFM per ton is a nominal desired CFM. Many 5 ton systems only have 1600 to 1750 CFM of actual air flow.

I would stay away from the one you posted. Unless your duct system is ideal. The blower in it is rated at a max 1800CFM at a .5" ESP. So if your duct system is under sized like most, you may not even gt 1600 CFM through it. And have your A/C coil freeze up at mild outdoor temps, and a higher electric bill because of the bower motor running at its highest RPM.
beenthere is offline   Reply With Quote
Old 10-07-2012, 05:50 PM   #5
Member
 
Join Date: Jul 2011
Location: Houston Texas
Posts: 1,061
Default

Confused about AC CFM on varying Furnaces


Thanks BT, no just looking. That caught my eye because I thought the rule of thumb was 400 square feet per ton.
__________________
digitalplumber is just a name for use here, I am not a plumber!
digitalplumber 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
Dual Furnaces mcatlett HVAC 1 07-30-2012 03:56 PM
What brand of furnaces do you work on? R u brand specific? Liberator HVAC 7 01-25-2012 08:17 PM
Confused about Sub Panel stqevo Electrical 28 10-01-2009 11:04 PM
Twinned Furnaces Questions MrControls HVAC 12 12-13-2008 10:09 AM
2 furnaces 1 thermostat clarnp49 HVAC 3 12-05-2007 08:12 PM




Top of Page | View New Posts

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