Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-03-2020, 11:19 AM   #1
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Noisy Air Conditioner, fixed.....

For most of my trailers use I used my ancient Armstrong unit.

Last summer it broke down in the middle of Texas so I had to replace it the same day.

I bought a Coleman Mach III, and while I'm satisfied with its performance, I wasn't satisfied with the noise it produced.

What I noticed is that with the interior shroud taken off it is much quieter.

So I concluded that it must be the turbulence that the shroud induces that makes the unit noisy.

I thought about it for a while, and thought maybe if I put a thin layer of insulation in the bottom of the plenum it would quiet the torrent of air.

Yesterday I went and bought a residential air filter and commenced to cutting it up. I chose a thicker one, about a half an inch thick, and put one of the pieces I cut into the bottom of the plenum, and another smaller piece was cut to fit over the vent that points toward the back of the trailer.

The result?

The noise the unit makes was cut DRAMATICALLY. Very comparable to my other trailer that has ducted air.

This is a very simple and inexpensive fix that made a huge difference, my real question is, why did Coleman miss such a simple, cheap, and effective fix? Click image for larger version

Name:	IMG_2907.jpg
Views:	79
Size:	254.0 KB
ID:	367094Attachment 1
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 05-03-2020, 11:22 AM   #2
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Noisy Air Conditioner, fixed.....

Quote:
Originally Posted by J. Morgan View Post
For most of my trailers use I used my ancient Armstrong unit.

Last summer it broke down in the middle of Texas so I had to replace it the same day.

I bought a Coleman Mach III, and while I'm satisfied with its performance, I wasn't satisfied with the noise it produced.

What I noticed is that with the interior shroud taken off it is much quieter.

So I concluded that it must be the turbulence that the shroud induces that makes the unit noisy.

I thought about it for a while, and thought maybe if I put a thin layer of insulation in the bottom of the plenum it would quiet the torrent of air.

Yesterday I went and bought a residential air filter and commenced to cutting it up. I chose a thicker one, about a half an inch thick, and put one of the pieces I cut into the bottom of the plenum, and another smaller piece was cut to fit over the vent that points toward the back of the trailer.

The result?

The noise the unit makes was cut DRAMATICALLY. Very comparable to my other trailer that has ducted air.

This is a very simple and inexpensive fix that made a huge difference, my real question is, why did Coleman miss such a simple, cheap, and effective fix? Attachment 367094Attachment 1


Here is the other picture that didn't post...Click image for larger version

Name:	IMG_3075.JPG
Views:	46
Size:	403.0 KB
ID:	367095
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 05-03-2020, 12:31 PM   #3
Rivet Master
 
Iansk's Avatar
 
1977 31' Sovereign
Vintage Kin Owner
Vintage Kin Owner
Sunset Valley , Texas
Join Date: Jul 2016
Posts: 744
Interesting,

So you are basically just filtering the air as it is blown back out and that cut the noise?
How much restriction do you think this added and what if anything do you think that will do to the performance and longevity of the unit?
Finally, where exactly did you put the material in the bottom of the plenum? Laid in a layer under the handler?

This could be a KISS solution, awesome.

Thanks,
Ian
Iansk is offline   Reply With Quote
Old 05-03-2020, 01:16 PM   #4
Site Team
 
Hans627's Avatar

 
2009 25' FB International
2018 27' Globetrotter
Tavares , Florida
Join Date: Mar 2014
Posts: 3,675
Great idea for a fix!

As to why did Coleman miss such a simple fix I would say they didn't miss it but chose not to add it for economic reasons. I'm not sure how many A/C's Coleman makes but let's assume it's a 1000 per week (not that many when you consider Ford makes 4000+ F-150's per day). If it cost's $1 for the filter material and labor to install it that's a savings of $50k per year.

So they decided to save a little money and most people will live with the noise (not realizing there are creative people who will make improvements).

Regardless, it's quieter now!
Hans627 is offline   Reply With Quote
Old 05-03-2020, 01:26 PM   #5
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Noisy Air Conditioner, fixed.....

Quote:
Originally Posted by Iansk View Post
Interesting,

So you are basically just filtering the air as it is blown back out and that cut the noise?
How much restriction do you think this added and what if anything do you think that will do to the performance and longevity of the unit?
Finally, where exactly did you put the material in the bottom of the plenum? Laid in a layer under the handler?

This could be a KISS solution, awesome.

Thanks,
Ian


Yes but no.

I placed the filter over the register to the rear of the trailer because I didn't need so much air back there anyway, but the front register isn't blocked, except where I placed the filter material on the floor of the interior shroud.

The unit still moves plenty of air forward, and a surprising albeit a reduced amount of air rearward even through the filter.

The unit itself discharges very close to the rear register, so I'm thinking that my covering this has adds to the quietness quite a bit, but fortunately for my trailer reducing the flow backward a bit actually helps.

The performance so far seems unaffected, I don't think that the longevity will be affected, if the unit were to tend to freeze up in use I might reevaluate, but in the near 24 hours it's been in place there is no indication of a freeze up at all.

I put the filter material along the entire discharge section of the interior shroud up to about 2" from the discharge vents.

Right now it's 96 outside and 72 inside...

I'll update this as the day progresses.

Being able to hold normal conversations from any point within the trailer is pretty dang cool.

(Edit. I should have mentioned that I used a separate piece of filter material to cover the rear discharge vent, I can reach my fingers through the vent slots to change the amount of the vent that's restricted).
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 05-04-2020, 07:06 AM   #6
Rivet Master
 
Iansk's Avatar
 
1977 31' Sovereign
Vintage Kin Owner
Vintage Kin Owner
Sunset Valley , Texas
Join Date: Jul 2016
Posts: 744
Thank you for the reply and further details. I’ll try this this week.

Ian
Iansk is offline   Reply With Quote
Old 05-04-2020, 07:20 AM   #7
Rivet Master
 
lsbrodsky's Avatar
 
2012 25' FB International
Trent Woods , North Carolina
Join Date: May 2013
Posts: 3,120
I read this yesterday and I am not sure I understand. Aren't you just reducing the amount of airflow over the coils and into the trailer? Are there any long term consequences of running your AC with less airflow than designed? It won't hurt the fan since that is just a centrifugal blower, but surely you have changed the delta T across the coil?
Larry
lsbrodsky is offline   Reply With Quote
Old 05-04-2020, 08:17 AM   #8
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Quote:
Originally Posted by lsbrodsky View Post
I read this yesterday and I am not sure I understand. Aren't you just reducing the amount of airflow over the coils and into the trailer? Are there any long term consequences of running your AC with less airflow than designed? It won't hurt the fan since that is just a centrifugal blower, but surely you have changed the delta T across the coil?

Larry


Not really.

What's happening here is the filter media is calming the turbulence that normally occurs when the air discharged by the unit impacts the floor of the interior shroud.

While it probably does restrict the air to a slight degree, it's not noticeable in its operation.

Could it somehow shorten the lifespan of the unit? Maybe, but I doubt that it restricts the air as much as ducting would so I doubt there will be any measurable consequence. But even if there is, being able to talk in normal tones makes it worth it to me.

If the fix causes the evaporator to freeze up, that would indicate an issue, but that hasn't happened yet.

If it does happen when it gets more humid I'll post up here, but it's not going to happen, the unit still moves a LOT of air.
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Reply


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
Noisy Air Conditioner WGreg Furnaces, Heaters, Fireplaces & Air Conditioning 1 04-06-2016 06:09 PM
Noisy Air Conditioner gtc6452 2011 - 2015 International 10 09-30-2011 03:02 PM
Noisy Air Conditioner Larry71 Furnaces, Heaters, Fireplaces & Air Conditioning 2 07-13-2006 01:01 PM
air conditioner air flow problem strawberryjo Furnaces, Heaters, Fireplaces & Air Conditioning 0 06-05-2006 10:43 AM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 04:41 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.