Air conditioners, the vent ducts are not working!!!

[rcpilot]

After all the vents, intakes, and front AC box were retaped and installed I removed the vent caps from the four Zone 1 ceiling vents and did a flow test with the fan on Hi. There was much more air moving than before. The vent caps were major restrictions to flow. Now you can feel the air moving standing under each vent.

If I started the fan in the front bedroom and closed the slide vent over the bed I could increase the flow to Zone 1 even more. I feel that closing several leaks and removing flow restrictions made Zone 1 much more effective in moving air.

The next step for Zone 1 mid cabin will be removing the AC from the roof and reworking the air box and duct inlets as mentioned earlier in the thread.

[rcpilot]

The last step from inside was to remove the AC vent cover over the bed in the garage. This is where I found the total mess and decided to post my findings on the forum.

As soon as I removed the air filter I found the electrical wire for the AC resting on the point of one of the mounting screws. A few more bumps and the screw would have penetrated the wire and shorted it out.

After removing the vent cover I could see all the way thru the air box from intake side to exit side. I found the rubber baffle was stuck sideways between the sides of the box. This allowed all exit air to be sucked right back into the intake side and made the exit air almost non existent. This is why we were never able to get much flow from this AC unit last summer. There are not ducts attached to this rear unit air box. I taped the baffle into position and sealed air leaks around the edges.

[rcpilot]

I use zip ties to bundle the rats nest of wires and remounted the thermostat wire which fell out when I dropped the bottom plate. After closing up the unit and testing there was much more airflow. It seemed best to close the slide vents on the bottom of the vent cover and open the exits on the front, back, and sides of the cover.

[rcpilot]

I really like the Voltage 3895 a lot. It fits our needs and uses quite well. However, there is a major issue with the design and quality control of the AC systems. I look forward to testing my work when the weather warms up.

The hazard I found was from poor installation of the electrical wire in the rear unit and the total failure of the baffle installation from the factory. I encourage all Voltage owners to inspect their ducts and front and rear AC units front the inside.

The last part of this project will be removing the center roof mounted AC and repairing the main air box and duct inlets. I'm sure I will find the mess there as was found inside today and was previously reported in this thread. I will report back with more pictures when I get it done.

[donzinger]

rcpilot - excellent write-up and description. This is one the projects I will tackle early spring as we gear up to go out for the season. Thanks!

[wahoonc]

Y'all make me glad I have a cheap trailer with non-ducted air.

I don't get the total lack of QC, I could see the occasional issue, but this is systemic and it isn't just Dutchmen.

Aaron

[calewjohnson]

Thanks for the write up and pics....I have pulled the center AC off the roof and fixed the air box when we first bought the trailer, however, I have not done much else...

I did cut some 1x2 strips and pushed into the sides of the Zone 1 air intakes to open them up. Mine was buckled to the point that I could not slide my fingers into the intake. Doing that alone increased air like a champ.

Cale

[Thom]

RCPilot,
Welcome to the forum!
Great first posts.

[rcpilot]

Roof AC removal.

Warmer and drier weather finally arrived and I got to the roof mounted AC. First step was to remove the plastic top shroud. There are several screws on the sides that were removed and the cover was flipped over and out of the way to the rear.

The AC unit is attached to the roof with four lag screws, two on front, and two just forward of the coils.

[rcpilot]

The lag screws were removed as shown. The screws were long. After removing the lag screws I traced the triangle pattern on the roof with a Sharpie marker to assist in reposition when done. I highly recommend doing this as it made replacement alignment easier.

[rcpilot]

I used a small throw blanket to protect the roof when moving the AC unit to the right of the holes.

To no one's surprise I found the expected mess of poorly applied HVAC tape and multiple air leak areas on both the intake and exit air boxes.

The wires come out of the intake side.

The sun angle was low so please excuse the shadows, I could not get out of the way.

[rcpilot]

The next step was to remove all of the factory applied tape. This tape was thin and poor quality. Then I re-taped and sealed all sides, corners and ducts in the exit air box.

This is where a baffle splitter should be installed to eliminate turbulence and allow the air to flow smoothly into each duct entrance, but I ran out of time. I may do it after testing this summer.

These photos show the exit air box after taping.

[rcpilot]

More after taping photos showing the exit and intake boxes. These air boxes are now air tight and do not have the air leaks anymore.

[rcpilot]

The last step before replacing the AC unit was to dress up the wire bundle with zip ties. This makes it much easier to replace the unit and I think it would make less air drag in the intake ducts. I highly suggest you check the thermostat unit down below before replacing the unit and make sure there are no error codes showing. I found an error code for lost communication. After checking the wires I found a loose phone plug in one of the thermostat wire connectors.

Replacing the AC unit was made easier by aligning the triangle drawn on the roof before with the hole in the bottom frame. Once it is close it is very easy to align the lag screw holes.

I found none of my four lag screws engaged anything except the OSB roof panels. There was no solid wood under the holes. Therefore do not over tighten when replacing the screws. I did the last turns by hand to feel the resistance when fully turned in.

[rcpilot]

After replacing the AC unit I tested the airflow inside the main cabin in Zone 1. I had much more air flowing from the ceiling vents than before. I regret that I did not measure the air flow before, so I could compare with the after. It would have been easy to do with my wind speed meter. However, in my subjective opinion there is much more air flowing now than before. The true test will be in hot weather this summer.

There are two other mods I may make if I feel there is need of more air.

1. Cut an intake vent directly below the AC down through the drop ceiling over the sink. This would greatly increase the intake area and allow more air into the system. More air in equals more air out!

2. Install a curved splitter baffle in the exit air box just under the blower. This would provide a splitter and smooth arc to flow air smoothly into each duct inside the exit air box. This would eliminate drag and turbulence inside the box and hopefully increase the air flow directly into the ducts on each side.

As I said before I really like the Voltage 3895 toy hauler and it is great for both our campground and dry camping use. I hope these repairs of poor factory manufacturing will help make the cooling better during the summer months. Also I hope my experience and photos will help others with the same issues.

Good luck and be safe.

[waytoogood]

Thanks for the great write up. What tape did you use and where did you buy it from?

[rcpilot]

I got the tape at Lowes or Home Depot. I think both have it. It's not cheap but is worth it.

Nashua is the brand I had on hand when I started from previous projects. I purchased another roll of 3M brand at Lowes with the same specs of UL181A-P & B-FX but did not need it. The tape is 2.5" wide and thicker than the factory tape. That stuff was like cheap tin foil.

I recommend the 2.5" wide tape instead of the narrower rolls. It gives better overlap on the seams. I also cut lots of 1" slices off for corners and curved areas as needed.

Good luck with your upgrade.

[arlan in arizona]

Originally Posted by rcpilot

I got the tape at Lowes or Home Depot. I think both have it. It's not cheap but is worth it.

Nashua is the brand I had on hand when I started from previous projects. I purchased another roll of 3M brand at Lowes with the same specs of UL181A-P & B-FX but did not need it. The tape is 2.5" wide and thicker than the factory tape. That stuff was like cheap tin foil.

I recommend the 2.5" wide tape instead of the narrower rolls. It gives better overlap on the seams. I also cut lots of 1" slices off for corners and curved areas as needed.

Good luck with your upgrade.

That's the tape I used when I re-taped my duct work. I bought it an Amazon like almost everything I buy. It is thick and super sticky. It also has a good amount of elasticity to it as opposed to the thinner tapes. Good stuff.

[RVNevada]

RC Pilot:

Thanks for all the hard work, and pictures, I have started working on my V3895, When I opened the front A/C from inside, all the electric boxes were just laying there, thank God the wires were long or all the wires would have disconnected….I know, like you I will find things wrong in the other 2 A/C
Thanks Again
Rich

[rcpilot]

Update from RCpilot…

We have now had a chance to ops check the cooling after the AC duct rebuild on the Voltage during hot weather. I am happy to report the air flow is significantly improved in all zones and cooling is much better.

The week before Memorial Day I had the Voltage in Wilson, NC for an RC jet event. Temps outside were 87-89. I was dry camping at the airport so there was no hook up available to run the AC during the day. At 7pm I went in to turn the AC on for the night. The inside temp was 95. By 8pm the inside temp was 75 and cooling well with just the Zone 1 and 3 (center and front) ACs running on generator power. Last year before the AC rework it would still be 85 after only an hour, so there was a much better air flow than before.

This last week we were in a campground in Myrtle Beach, SC for the week with full 50 amp hookup. We used all three zones. My wife commented on how much better the system was cooling than last year. She could feel the air flow from the recliners in Zone 1. Last year you could not feel any air flow and we had a box fan blowing from the loft all the time. Now there is no need for the fan.

I still want to test the system in really hot weather i.e. 95-100 OAT. This will really be the test.

I still think the air intake area should be larger and have considered cutting an intake duct straight down through the drop ceiling and putting a grill and filter on it, however I want to see how it works this year first, especially during hot OATs.

I will keep you posted as temps rise this summer.

Be safe out there!