Go Back   iRV2 Forums > MOTORHOME FORUMS > MH-General Discussions & Problems
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 06-16-2016, 06:03 AM   #1
Senior Member
Waiter21's Avatar
Forest River Owners Club
Ford Super Duty Owner
Join Date: Nov 2014
Location: Toledo, OH
Posts: 1,589
Beat the heat - improve air flow from ceiling AC unit

I’ve always had a concern about the roof top AC unit. It seemed like it doesn't put out the quantity of air that it should.

Last week I was removing the AC unit in preparation for re-coating the roof. I looked carefully at how the air flow is routed, and wasn’t happy with what I seen.

With the ceiling cover off I ran the AC unit. The large squirrel cage blower delivers a lot of air, straight down toward the floor. However, when the ceiling cover is installed, the air enters into the ceiling unit, and is restricted by abruptly 90 degree turn and a 2 inch restriction. the air then takes several more 90 degree turns before it exits out the vents on each end.

What the cover really needs is a vent opening just below the blower that allows the air to shoot straight down toward the floor, unrestricted.

See entire article with photos below.

Beat the heat – Improving air flow from the air conditioner ceiling unit | 2001 Coachmen Mirada 300QB

Attached Thumbnails
Click image for larger version

Name:	AC_Vent_1_800.jpg
Views:	121
Size:	156.2 KB
ID:	130359   Click image for larger version

Name:	AC_Vent_4_800.jpg
Views:	121
Size:	56.1 KB
ID:	130360  


2001 Coachmen Mirada (Ford F53 6.8L V10) - Toad 2003 Saturn Vue.
It won't do MACH 2, but I can get a sandwich and take a pee.
Waiter21 is online now   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 06-16-2016, 08:25 AM   #2
Senior Member
530ktm's Avatar
Join Date: Dec 2014
Location: SoCal
Posts: 1,188
Interesting project. I have never been impressed with the ducted system and I put some deflectors in my vents to help direct air down where it should be. Seems a lot of the cold air just passes over the openings as they are. When it is hot this could be a good idea to simply blast some good cold air inside the coach for a while and I am going to check it out with mine.

2014 Itasca Sunova 33C towing a Jeep TJ Wrangler
530ktm is online now   Reply With Quote
Old 06-16-2016, 08:44 AM   #3
Senior Member
Waiter21's Avatar
Forest River Owners Club
Ford Super Duty Owner
Join Date: Nov 2014
Location: Toledo, OH
Posts: 1,589
I understand some of the newer ducted systems may already have a louvered vent near the intake that does exactly this. My system is unducted and older, and this made a BIG difference.
2001 Coachmen Mirada (Ford F53 6.8L V10) - Toad 2003 Saturn Vue.
It won't do MACH 2, but I can get a sandwich and take a pee.
Waiter21 is online now   Reply With Quote
Old 06-16-2016, 01:07 PM   #4
Senior Member
Brian W's Avatar

Fleetwood Owners Club
Ford Super Duty Owner
Join Date: Mar 2014
Location: Bartlett, TN
Posts: 1,046
The plenums for my ducted system have louvers on 3 sides I can open to dump the air straight out. We do this on both units until we get the coach to the desired temp. Once there, we close the louvers and use the ducts.
Brian and Tammy
2014 Fleetwood Bounder 35K
Mercury Mariner Hybrid
Blue Ox Baseplate, Blue Ox Tow Bar, Patriot Braking
Brian W is online now   Reply With Quote
Old 06-16-2016, 02:40 PM   #5
Join Date: Jan 2016
Posts: 66
I have what looks like the exact same AC unit. I guess I've got another project now

I assume the thought behind the original design is that it blows along the ceiling, cooling the air that's collected up there. Blowing it straight down would mean that there's more cool air low down, but not a lot at head height. It'll probably cool the coach more effectively anyway, just by virtue of putting out more volume.

1990 Glendale Royal Classic
2005 Jeep TJ Rubicon
stevemoores is offline   Reply With Quote
Old 06-16-2016, 03:24 PM   #6
Senior Member
YC1's Avatar

Holiday Rambler Owners Club
Join Date: Jun 2011
Posts: 4,570
I have done many variations and it does work., However the noise level can be a pain.

Drop your round registers out and see if they are a bit too long inside the ducts., I trimmed all of mine for a better fit.,

In addition to that I lined the transition area inside the AC's with metal duct tape to smooth out the air flow.

My condensation units need to be cleaned well about every 6 months. I am full time and in Florida so the AC runs a lot.

Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate
YC1 is offline   Reply With Quote

ceiling, heat

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
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
Low floor heat air flow bobbyl Winnebago Industries Owner's Forum 15 01-27-2014 07:17 AM
Do air bags on the pickup help improve chucking from the 5ver? BriaLynne 5th Wheel Discussion 33 10-27-2013 07:45 AM
Finally Able To Beat The Heat 62_inrightlane Class A Motorhome Discussions 15 02-25-2013 02:48 PM
Is there a way to improve the speed on a AT&T air card in remote areas? StansCustoms Alpine Coach Owner's Forum 26 07-16-2011 03:27 PM
Beat the Texas heat Elkhartjim Texas Boomers 15 07-21-2009 06:30 AM

» Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 07:09 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.