Repaired A/C Installation

[rob_fla]

While going through our rear A/C unit checking all the seals and fasteners to correct a water leak we have in our Rear Bedroom Light fixture I found another issue with the A/C unit installation

What I found was the foam that fills the space and seals between the Air Conditioner intake / return from the registers and supply to the vents.

With this foam out, the air flow just circulates in a loop from the supply side back to the return side of the A/C unit.

This will make a significant difference in the A/C Unit performance.
This would explain why we had problems with our A/C keeping up during the summer heat here in the South.

Rear A/C unit with foam seal out of cavity


Front A/C unit with the foam strip out of cavity



Rear A/C unit with foam replaced and foil tape applied to keep it sealed between the supply and return.

[johnboytoo]

A buddies heartland had the same issue !!!

basically the return was sucking in the cold air and it wasn't taking it from the coach !

[rob_fla]

Yep, instead of sucking the warm air in from the filter grills and cooling it, the cold air from the supply is going back into the intake side.
Hope the A/C system works better when the warm summer air gets here, it should work quite a bit better.

[atom ant]

Curious how you accessed that part of the AC? Did you pull down ceiling?

[Fredtp]

I had the same question Atom.

[rob_fla]

Originally Posted by atom ant

Curious how you accessed that part of the AC? Did you pull down ceiling?

Nope AA, you go up on the roof, remove the top / outside plastic cover from the A/C unit, then remove the front metal cover on the A/C unit and it exposes the intake side (you can see all the way down to the roof intake plenum) and front side of the cooling coils that the air is sucked through.
In the center you will see the divider between the two sides of the A/C unit (Intake & Supply). The Roof framing requires a gasket / seal of some type to keep the two cavities divided so they use a piece of foam with sticky tape on one side to hold it in place. The tape did not hold and the foam got sucked up into the cooling coils on the intake side.
(On the front unit, the Romex wire for the A/C unit power was embedded in the foam gasket that seal the two cavities.)

I always wondered when one unit was running why I could feel air blowing out the side intake registers of the other unit.
Now that the A/C units have been sealed between the intake and the supply output like they should be, we have a much better air draw at the side intake registers with the filters and now I do not feel any air coming out of the intake registers of the unit that is not running.

Since temperatures have been very mild the last few days, will not be able to see if the fix will improve A/C performance but I believe it is going to make a significant difference in our A/C performance.

[atom ant]

Thanks Robert! I feel much better that these can be serviced now. I used to think they had to be removed from the roof to access anything on the bottom.

[rob_fla]

Originally Posted by atom ant

Thanks Robert! I feel much better that these can be serviced now. I used to think they had to be removed from the roof to access anything on the bottom.

AA, it looks like you can service and clean the coils on the intake side and access all electrical components from the top, it appears the only thing with no access from the top without removing the unit is the supply area and duct plenum below.

[rob_fla]

Originally Posted by johnboytoo

A buddies heartland had the same issue !!!

basically the return was sucking in the cold air and it wasn't taking it from the coach !

I could see this issue on one unit as a mistake at assembly, but I had the same issue on both units.

Guess I would find it hard to believe I am the only Redwood owner with this issue, makes me wonder if some of the other forum members that have had A/C performance issues in the hotter climates have the same problem?

[travelin' texans]

That's the great part of this forum, someone figuring out their own issues & a relatively simple solution & sharing it with all of us. It sure has saved my bacon several times. I would like to give all a great big ATTABOY!!

[BasilFawlty]

We had the same problems on both A/C units (2015 38RL). Fixed it first with normal duct tape and then again two days later with stronger tape. However - we suspect that there is more things wrong since we feel that the unit is working all the time and still can not keep up even if outside temp. is 75 degrees. Since we took deliver we can not remember that even with both A/C working that the temperature inside. With two A/C servicing 400 sqft it should be a refrigerator inside if they are working continuously.

What is your experience? Maybe worth a professional service trip?

[mhs4771]

We've been able to maintain lower 70s even when outside temps were pushing 100.

[BasilFawlty]

Thanks Michelle & Ann!! - then I think we have a problem.

Need to change roof and are waiting for Redwood to get us in for that warranty repair so will try to make all at the same time.

[rob_fla]

I have also done a couple of other A/C system mods previously that have improved the A/C system performance.

I think one of the reasons that helped get the foam gasket pushed out is too much back pressure on the supply side of the system when both A/C units are running.

Our 38 FL had 3 ceiling registers on the right side duct and 4 ceiling registers on the left side duct plus all the 7 of the registers and had sleeves that stuck 1 1/2 inches up in the ducts therefore blocking quite a bit of air flow from going down the ducts.
To me, at total of 7 ceiling registers for two 15K A/C units is not enough to get proper air flow when both units are running in high speed and having more ceiling registers on one duct than the other does not make any sense at all.

I added 2 ceiling registers on the right side duct and 1 ceiling register on the left side duct to add air flow and balance the duct system.
We now have 5 ceiling registers on each duct line and I cut down the register sleeves that extended into the duct so they only extend into the duct approx. 1/2 inch instead of 1 1/2 inches.

So with our current A/C system we have much better air flow from the ducts and now with the repaired foam seal between the supply and return plenums our system is working much better now.

Now we just need a hot day to confirm the performance improvement.

[rob_fla]

Originally Posted by BasilFawlty

We had the same problems on both A/C units (2015 38RL). Fixed it first with normal duct tape and then again two days later with stronger tape. However - we suspect that there is more things wrong since we feel that the unit is working all the time and still can not keep up even if outside temp. is 75 degrees. Since we took deliver we can not remember that even with both A/C working that the temperature inside. With two A/C servicing 400 sqft it should be a refrigerator inside if they are working continuously.

What is your experience? Maybe worth a professional service trip?

Our unit would keep up at 85 degrees outside with no problem but when temperatures went above 85 degrees outside it struggled to keep up.

For me to take our RW in for service, the closet dealer is 250 miles and my faith in the typical service department getting things done right is pretty poor.
Even at delivery I had to show the service tech what needed to be repaired and follow up to be sure they even did the repairs.
For example, the tech did not have any idea how to fix the Bauer keyless locks and just threw his hands up, I corrected the installation issues with the Bauer Keyless locks and both of them have preformed flawlessly since.
I can make the repairs my self on most items in less time than it takes me to drive the 250 miles one way to the dealer.

I will say that I have sent Jim Lazzarino some of my pictures and write ups of our repairs and mods, he has always responded with a short email saying he is forwarding the info to his team.
I do not know if it is doing any good but I sure hope it makes a difference, since many of the issues I have run into are not isolated to our RW only.

[rob_fla]

Even though the weather has not been all that warm as of yet, the A/C units sure seem to be preforming better.

Also we have had a couple of good steady rains over the last few days, I left the left rear ceiling light fixture out so the insulation would dry out and I could also reach up into the ceiling cavity to see if it was getting wet again.
So far, the insulation is completely dry, no dampness / moisture / water at all.

[atom ant]

Robert,

Do you have the heat pumps? Seams like they would perform better in that mode too.

[rob_fla]

Yep AA, we have the single Heat Pump on the rear A/C unit over the bedroom and the Fireplace in the Front Living Room, makes for a good combo since the front A/C unit is not a Heat Pump, it is just a standard A/C.

You are right the heat pump works better too.

Ya gotta love Florida weather, 80 degrees last week, 40 degrees this week so the rear heat pump is running right now and doing a great job keeping the whole coach warm by its self.

[Benelli]

We have a 2014 38RL and live in Dallas TX. Our bedroom will not get below 85 degrees in the summer and 2 of the four vents have minimal air flow coming out. I have it at the dealer now for warranty work and they are checking it out. I will let them know what you found and see if it is my issue.

Great Update!!!

[BasilFawlty]

Thanks, will look out for your post.