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

Go Back   iRV2 Forums > TRAVEL TRAILER, 5th WHEEL & TRUCK CAMPER FORUMS > 5th Wheel Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  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 08-10-2022, 08:29 PM   #43
Junior Member
 
Join Date: Aug 2022
Posts: 10
I have a solution

After not being able to cool my coach I installed the third mid-ship 15K air conditioner, plus the second awning in an attempt to cool it down. These efforts (and expenses) really had no effect on cooling down the coach. Regardless of what I did, in 90 degrees or better heat, I could never get below 80 degrees; and this is just not comfortable.

The first idea I wanted to try was making a custom plenum box. The existing box is what appears to be typically used in the industry. It turns out this is highly ineffective as it is a horrible way to direct air. This is what I did:

First, I pulled the rear-most air unit. I was cursing the entire time as both the air conditioner and the roof were glued to the gasket/seal. From what I have now learned, this is not the proper way to do this. Only one is supposed to be attached to the gasket and the other is just a compression fit. I spent over 6 hours removing the air conditioner and gasket. This was really an unnecessary job.

The plenum box looks like this:






In the above pictures, you can see that the air actually has to fight to get into the small opening of the vent. You have a vertical wall above and below the vent that does not assist this effort at all.

Pretty standard from what I have seen during my research into this issue. But, this is not an efficient way to move air at all it turns out. The air conditioner sits atop the plenum box and slams air into the box. The air moves around until it finds the opening (vent) and finally moves down the line.

I decided to make a custom plenum box that fits into the existing box. My box would funnel the air directly into the vent eliminating the chaos of air slamming around the plenum.

I started with a piece of foam between hard paper that I purchased at my local craft store. I cut it to the size of the floor of the plenum box. Prior to placing it, as it was too thin and would have left me with part of the vertical wall, I placed two shims to bring the bottom of the floor to the exact height of the vent.





Then the floor



As you can see, the floor Is now on the same plane as the vent. A little silver foil tape and on we go.


Next was this back wall. I scored the back of the piece so there would be a slope to it; again, guiding the air to the vent.



Some more foil tape and on we go



I then cut a piece to fit atop the plane of the top of the vent, setting it at an angle to meet the air conditioner once it is reinstalled.



Once the air conditioner was reinstalled, everything was silver taped to provide a clean, smooth surface to guide and direct the air directly into the vent (I had to remove the fan & motor assembly to tape everything).




So, let’s talk number because all of this is moot if I can’t back it up (and I can).

I purchased a digital anemometer and took lots of readings both prior to any modification and after. Here are my results:

Rear Zone Air Conditioner – No modifications:

Rear roof vent: 700 Feet per Minute
Mid roof vent: 900 Feet per Minute
Front roof vent: 787 Feet per Minute

Total Feet per Minute: 2431

With the new custom plenum box:

Rear roof vent: 706 Feet per minute
Mid roof vent: 1201 Feet per Minute
Front roof vent: 1142 Feet per minute

Total feet per Minute 3049

Difference: An increase of 25% airflow

I did the same upgrade to the mid-coach air conditioner. Here are those results:

Mid Zone Air Conditioner – No modifications:

Rear roof vent: 334 Feet per Minute
Mid roof vent: 137 Feet per Minute
Front roof vent: 433 Feet per Minute

Total Feet per Minute: 904 Feet per Minute

With the new custom plenum box:

Rear roof vent: 590 Feet per Minute
Mid roof vent: 216 Feet per Minute
Front roof vent: 1004 Feet per minute

Total feet per Minute: 1810 Feet per Minute

Difference: An increase of 100% airflow*

*This number may be a little off as when I pulled the middle air conditioner I noticed the “technician” that put it up failed to place the foam barrier above the metal separating wall between the return air and cooled air.

I did notice an anomaly that I didn’t expect and was actually quite shocking to me. Air is being sucked back into the vent while using the air conditioner. When using the rearmost unit, the cooled air comes out of the vent at the front edge of the roof vent. I can place my hand and feel in the middle of the vent there is no air coming out at all. And, the digital anemometer showed the air is actually being sucked back into the vent. This should not be happening and it happens at all three vents. I took a video of this which you can see here:

https://photos.google.com/share/AF1Q...x4MXZNZnl6SU9n

This is really bizarre to me and someone much smarter than I needs to figure out how and why this is occurring. But, if the unit is delivering cooled air and then sucking it out, then this cannot be very efficient.

But, I wasn’t done yet. I was curious to see if I could even do better. I was not sure why when using the rear air conditioner there wasn’t what I considered a lot of air coming out if the rear roof vent. So, I tried a little experiment and wow, the results are amazing. I placed a block, actually some silver tape in the middle of the air vent at the front of each vent. Holy crap, did this change the air flow:



Man, this was crazy how much more efficient this was. Here are the numbers:

Rear roof vent: 1575 Feet per Minute
Mid roof vent: 960 Feet per Minute
Front roof vent: 964 Feet per minute

Total 3499 Feet per Minute

This is an increase of 450 Feet per Minute over and above the plenum box modification. But, I still wasn’t done. I had seen where some folks were putting short pieces of PVC pipe inside the vent to provide more space. My vents seem compressed to me and are just 13/16ths at the smallest measurement. So, I cut 6 2&1/2” PVC pieces in 2” lengths and shoved them inside my vent, raising the top of each vent. The numbers speak for themselves:

Rear vent with tape and pipe: 1732 Feet per Minute
Mid vent with tape and pipe: 1122 Feet per Minute
Front vent with tape and pipe: 846 Feet per Minute

Total 3700 Feet per Minute

I started with 2431 Feet per Minute and ended up with 3700 Feet per minute a 52% total increase in airflow on the rear unit alone! Imagine the rear and mid-air units on at the same time?

The total cost was around $20.00 in silver tape and foam board. If the air conditioner isn't glued to the roof (via the gasket) then it should take around two hours per air conditioner. I hope this helps folks.

steve
steveswitz is offline   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 08-11-2022, 11:03 AM   #44
Senior Member
 
beerdude's Avatar
 
Tiffin Owners Club
Texas Boomers Club
Join Date: Nov 2020
Location: Springtown, TX
Posts: 215
Quote:
Originally Posted by steveswitz View Post
This is what I did: <snip>
Incredibly helpful and thoughtful post, Steve.

IMHO also worthy of a new thread and stickied at the top of the Tiffin forum here where fully ducted/enclosed A/C's seem to be the norm. At a minimum this issue seems to be very common across the Vanleigh 5er brand.

Regardless, many thanks!
Greg
__________________
2021 Vanleigh Vilano 320 GK
2018 GMC Sierra 3500HD SLT Duramax 4x4 CCSB
beerdude is online now   Reply With Quote
Old 08-11-2022, 11:49 AM   #45
Junior Member
 
Join Date: Aug 2022
Posts: 10
Quote:
Originally Posted by beerdude View Post
Incredibly helpful and thoughtful post, Steve.

IMHO also worthy of a new thread and stickied at the top of the Tiffin forum here where fully ducted/enclosed A/C's seem to be the norm. At a minimum this issue seems to be very common across the Vanleigh 5er brand.

Regardless, many thanks!
Greg
Thanks for that. If it wasn't for the air conditioner glued to both the gasket and roof, this actually would have been a pretty casual modification effort-wise. There are 4 Phillips head screws that hold the cover on. Then there are only 4 bolts that attach the air unit to the roof. Once unbolted, you just lift the air unit off and set it aside. I realize most folks don't have the middle air conditioner so this plenum box modification, the tape or other type of blockage in the vent, and the PVC make it very worthwhile. And, the air still travels down the vent to the bathroom and bedroom if it is the only unit in operation. But, it is not the bedroom that is the issue; it is the living room! I can't stress enough how much of an improvement this is to the stock setup. The front air conditioner works so well I decided not to do the modification.

I started looking at other brands prior to these modifications. That is off-the-table now as I am very satisfied with the entirety of the coach now. I have made some other modifications (Disk brakes, New rims to take TPMS sensors, Better tires, etc) that have made this a really great coach.

If anyone tries this and finds the air conditioner glued both to the unit and roof, I would suggest using two people. One can't just pull up on the air conditioner as you will pull the roof membrane off the plywood. The only way I could figure out how to separate them was to use thin steel wire, push it through the gasket and pull it back and forth to slice through the gasket. I worked my ass off doing this. Two people would have made it easier.

As far as the "sticky" post goes, I can't see how to do this.

Steve
steveswitz is offline   Reply With Quote
Old 08-11-2022, 12:07 PM   #46
Senior Member
 
beerdude's Avatar
 
Tiffin Owners Club
Texas Boomers Club
Join Date: Nov 2020
Location: Springtown, TX
Posts: 215
Quote:
Originally Posted by steveswitz View Post
As far as the "sticky" post goes, I can't see how to do this.
That's an admin/moderator action, and should they agree with my suggestion they'll reach out and assist. May or may not meet their criteria, though, but I think it's great info nonetheless, and I'm sure many others will feel the same.
__________________
2021 Vanleigh Vilano 320 GK
2018 GMC Sierra 3500HD SLT Duramax 4x4 CCSB
beerdude is online now   Reply With Quote
Old 08-14-2022, 09:38 AM   #47
Senior Member
 
beerdude's Avatar
 
Tiffin Owners Club
Texas Boomers Club
Join Date: Nov 2020
Location: Springtown, TX
Posts: 215
Was cleaning the AC intake vents/foam filters today and felt around inside the ducting. Looky what I found.

They're loose in the ducting mostly. Only the pressure of insulation and roof pressing down on ducting to keep them in place. One was cocked diagonally. Not good but thankfully they're not big enough to fully shut off airflow even if turned fully sideways. I'll put a little piece of double-sided tape to help keep them in place.

One was missing, not counting the ones intentionally missing at the far ends of the ducting. Not sure if it was missed at install or if it shifted down the ducting beyond where my phone camera can see. I don't have a scope at the moment. May get one though.

r3842id mentioned in post #30 there was a late model (2022?) addition of Styrofoam spacers to help keep the ducting from collapsing, but it appears my 2021 has aluminum rectangular tube. Probably identical to what is use in the walls. (Can pick this stuff up at a big box store, I'm sure.)

So, I'm not 100% sure if they were factory installed (interim change?) or if Tishomingo service center added them when I said my AC was weak and had them install the 3rd AC. They didn't inform me they added any ducting spacers, but who knows. They're there now, minus one.

BTW the outflow side ducting does not have these spacers, at least mine doesn't. Might be intentional since the outflow side ducting is much narrower and doesn't look to be as susceptible to collapsing. You could still add spacers there too of course.
Attached Thumbnails
Click image for larger version

Name:	20220814_074859.jpg
Views:	5
Size:	215.2 KB
ID:	373606   Click image for larger version

Name:	20220814_080755.jpg
Views:	5
Size:	216.7 KB
ID:	373607  

Click image for larger version

Name:	20220814_080811.jpg
Views:	5
Size:	241.9 KB
ID:	373608   Click image for larger version

Name:	20220814_080827.jpg
Views:	6
Size:	216.9 KB
ID:	373609  

__________________
2021 Vanleigh Vilano 320 GK
2018 GMC Sierra 3500HD SLT Duramax 4x4 CCSB
beerdude is online now   Reply With Quote
Old 08-14-2022, 11:06 PM   #48
Junior Member
 
Join Date: Jul 2021
Posts: 7
On going A/C Issue

Steve and BeerDude your posts are awesome.

I have been checking out the Duct on my 2020 Vilano 320GK and the walls on the output ducts seem to be in place and OK. there didn't appear to be any ducting walls on the return vents/duct the ceiling was 1/8-1/4 inch from the bottom. So I put some styrofoam from a tv I just bought and seems to have increased the return duct spacing. doesn't get hot enough in the NW to really test.

I do seem to have the following issue and would be interested if you guys have this issue. A/C seems to put out air that is 20 degrees cooler than the coach but as Steve has pointed out the volume of air coming out is not great. as my coach slowly cools down on Auto Fan (starts at High Fan) once it gets within 1-2 degrees of the set temperature it switches to low Fan and when it does the Compressor sounds like it shuts off but there doesn't seem to be any decrease in the fan speed/Noise. but within 5 minutes the air coming out of the output ducts is the same as the input duct. so it stops cooling until it starts warming up and switches back to high Fan. I am working with Vanleigh and Airxcel but they aren't much help yet. Do you guys have this issue.

Steve, you are doing the mods yourself does Vanleigh have any consideration for paying to have an RV repair place do the mods?

thanks
lringstad52 is offline   Reply With Quote
Old 08-15-2022, 06:15 AM   #49
Junior Member
 
Join Date: Aug 2022
Posts: 10
Quote:
Originally Posted by lringstad52 View Post
Steve and BeerDude your posts are awesome.

I have been checking out the Duct on my 2020 Vilano 320GK and the walls on the output ducts seem to be in place and OK. there didn't appear to be any ducting walls on the return vents/duct the ceiling was 1/8-1/4 inch from the bottom. So I put some styrofoam from a tv I just bought and seems to have increased the return duct spacing. doesn't get hot enough in the NW to really test.

I do seem to have the following issue and would be interested if you guys have this issue. A/C seems to put out air that is 20 degrees cooler than the coach but as Steve has pointed out the volume of air coming out is not great. as my coach slowly cools down on Auto Fan (starts at High Fan) once it gets within 1-2 degrees of the set temperature it switches to low Fan and when it does the Compressor sounds like it shuts off but there doesn't seem to be any decrease in the fan speed/Noise. but within 5 minutes the air coming out of the output ducts is the same as the input duct. so it stops cooling until it starts warming up and switches back to high Fan. I am working with Vanleigh and Airxcel but they aren't much help yet. Do you guys have this issue.

Steve, you are doing the mods yourself does Vanleigh have any consideration for paying to have an RV repair place do the mods?

thanks
I am doing the repairs and research myself. As I stated previously if the air conditioner isn't attached/glued down on both sides it is about a two-hour job and costs next to nothing. I have been in touch with Vanleigh regarding my findings.
steveswitz is offline   Reply With Quote
Old 08-15-2022, 06:17 AM   #50
Junior Member
 
Join Date: Aug 2022
Posts: 10
Quote:
Originally Posted by beerdude View Post
Was cleaning the AC intake vents/foam filters today and felt around inside the ducting. Looky what I found.

They're loose in the ducting mostly. Only the pressure of insulation and roof pressing down on ducting to keep them in place. One was cocked diagonally. Not good but thankfully they're not big enough to fully shut off airflow even if turned fully sideways. I'll put a little piece of double-sided tape to help keep them in place.

One was missing, not counting the ones intentionally missing at the far ends of the ducting. Not sure if it was missed at install or if it shifted down the ducting beyond where my phone camera can see. I don't have a scope at the moment. May get one though.

r3842id mentioned in post #30 there was a late model (2022?) addition of Styrofoam spacers to help keep the ducting from collapsing, but it appears my 2021 has aluminum rectangular tube. Probably identical to what is use in the walls. (Can pick this stuff up at a big box store, I'm sure.)

So, I'm not 100% sure if they were factory installed (interim change?) or if Tishomingo service center added them when I said my AC was weak and had them install the 3rd AC. They didn't inform me they added any ducting spacers, but who knows. They're there now, minus one.

BTW the outflow side ducting does not have these spacers, at least mine doesn't. Might be intentional since the outflow side ducting is much narrower and doesn't look to be as susceptible to collapsing. You could still add spacers there too of course.
Wow, I understand why the spacers were there but wonder who put them in. I believe these rectangular ones would be better than a PVC pipe. I used a camera scope and didn't find anything in my ducts. With that said, I believe the ducts are an issue. How much cold air is exhausted out of the coach? Think about the design: Let's say one air conditioner is used. This unit is blowing air down the ducting system. What is at the other end? Another plenum box with a big hole where the fan is for the other air conditioner. This cool air is now escaping via the opening for the fan on air conditioner two. I am not faulting Vanleigh for this (I believe this is the standard industry design) but without a gate valve, this cool air goes bye-bye.

And, because this is an open system, there is no back pressure to force the air out of the ducts. The only way the air can escape through the vents is just by chance as it goes past. There really should be several gate valves and depending on what air conditioner is being used they are either open or closed. This certainly adds complexity but would also add efficiency and back pressure.

Finally, I would love for someone to be able to figure out the formula if the ducts, as designed, can take the amount of air that the air conditioner can throw down them. The air conditioner fan is rated at however many feet per minute and the ducting, based on the size, can handle however many feet per minute. I am not a heating and air guy so I don't know this formula.

Between all of us, this issue will have answers and a fix.
steveswitz is offline   Reply With Quote
Old 08-15-2022, 01:02 PM   #51
Senior Member
 
beerdude's Avatar
 
Tiffin Owners Club
Texas Boomers Club
Join Date: Nov 2020
Location: Springtown, TX
Posts: 215
Quote:
Originally Posted by lringstad52 View Post
...as my coach slowly cools down on Auto Fan (starts at High Fan) once it gets within 1-2 degrees of the set temperature it switches to low Fan and when it does the Compressor sounds like it shuts off but there doesn't seem to be any decrease in the fan speed/Noise. but within 5 minutes the air coming out of the output ducts is the same as the input duct. so it stops cooling until it starts warming up and switches back to high Fan. I am working with Vanleigh and Airxcel but they aren't much help yet. Do you guys have this issue.
I don't have that particular issue. Something seems wrong there. Unfortunately I don't have any definitive knowledge on how our AC systems are configured between the Spyder touch panel, G6A house panel, and Coleman AC units, and what calls for what.

My guess would be that either a) something is up in a Coleman circuit board, or b) the Spyder touch panel may need a reset? Purely guesses on my part. Has your AC unit always operated in this manner?

On my RV: When in Auto fan mode with AC on, I can definitely hear mine go from high fan speed (actual temp >2 deg away from set temp), to low fan speed (actual temp <2 deg from set temp), and once set temp is reached the compressor and fan shut off simultaneously with no fan run delay. Compressor is otherwise running 100% of the time when the fan is running at any speed.
__________________
2021 Vanleigh Vilano 320 GK
2018 GMC Sierra 3500HD SLT Duramax 4x4 CCSB
beerdude is online now   Reply With Quote
Old 08-15-2022, 01:06 PM   #52
Senior Member
 
beerdude's Avatar
 
Tiffin Owners Club
Texas Boomers Club
Join Date: Nov 2020
Location: Springtown, TX
Posts: 215
Quote:
Originally Posted by steveswitz View Post
Think about the design: Let's say one air conditioner is used. This unit is blowing air down the ducting system. What is at the other end? Another plenum box with a big hole where the fan is for the other air conditioner. This cool air is now escaping via the opening for the fan on air conditioner two. I am not faulting Vanleigh for this (I believe this is the standard industry design) but without a gate valve, this cool air goes bye-bye.
After seeing your photos, I was having similar thoughts about inefficient air handling at that center AC mount area without a middle AC unit present, and am glad I had the middle AC installed.

Edit: Had to reread your comment. Sounds like even with the units installed, though, there still may be some issues with disadvantageous crossflow between ducts? Argh.
__________________
2021 Vanleigh Vilano 320 GK
2018 GMC Sierra 3500HD SLT Duramax 4x4 CCSB
beerdude is online now   Reply With Quote
Old 08-25-2022, 05:12 PM   #53
Junior Member
 
Join Date: Jul 2021
Posts: 7
low fan cooling issue

Quote:
Originally Posted by beerdude View Post
I don't have that particular issue. Something seems wrong there. Unfortunately I don't have any definitive knowledge on how our AC systems are configured between the Spyder touch panel, G6A house panel, and Coleman AC units, and what calls for what.

My guess would be that either a) something is up in a Coleman circuit board, or b) the Spyder touch panel may need a reset? Purely guesses on my part. Has your AC unit always operated in this manner?

On my RV: When in Auto fan mode with AC on, I can definitely hear mine go from high fan speed (actual temp >2 deg away from set temp), to low fan speed (actual temp <2 deg from set temp), and once set temp is reached the compressor and fan shut off simultaneously with no fan run delay. Compressor is otherwise running 100% of the time when the fan is running at any speed.
Working with Airxcel I have resolved this issue. Looks like the factory installed the Cooling on/off wire and the high fan wire backwards. once I reversed them the fan issue is gone. now hopefully I can resolve the air flow issue with some of Steve's suggestions
lringstad52 is offline   Reply With Quote
Old Today, 03:45 PM   #54
Junior Member
 
Join Date: Aug 2022
Posts: 10
It Works!

This weekend is the first week we have taken the 5th wheel out since the air modification. I am happy to report that it WORKS! For the 1st time since owning our Vanleigh, I have been able to keep it cool in the 70's. We are in Willits California right now and it is around 85. The coach is now very cool, and comfortable; the airflow is noticeably stronger and cooler. I am so pleased with the air conditioning system now. Before the modifications, I was considering selling it. I can't recommend these modifications enough.
steveswitz is offline   Reply With Quote
Reply


« Speed limits | - »

Currently Active Users Viewing This Thread: 2 (0 members and 2 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
2021 Vanleigh Vilano 320 GK :: 2021 Vanleigh Vilano 320 GK beerdude iRV2 Owners Registry 0 12-15-2020 05:10 AM
Vanleigh Vilano 375FL :: 2018 Vilano 375fl brunter iRV2 Owners Registry 0 06-14-2020 06:12 PM
Possible Vilano 320GK in our future Steelie53 iRV2.com General Discussion 11 06-25-2019 08:12 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 05:56 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.