Cheap A/C improvement

[Lt Keefer]

Small things can add up. I did a couple of improvements that have cooled down the coach while running on 1 A/C. First, I installed one of those foam pillow things in the living area ceiling vent. Next I took out the last ceiling vents at both ends of the coach and blocked the excess duct work with pieces of foam. What a big difference it makes. We are camping just outside of Dallas and the one A/C has no trouble keeping the inside of the coach at 75 degrees.

[Bob Denman]

Congratulations! Do you have any pictures to show us?
(My head is easier to wrap around a concept; once I've seen some pictures...

[Thalupa]

I agree send some pictures what is a foam pillow thing ???

[nosticks]

The pillow thingie is a vent insulating pillow 14"x14"x3". You stuff it in the vent opening and it insulates the area above it. Just go to Amazon and put in "rv vent pillow".

And come on, pictures of a piece of foam cut to block off the duct end runs? I bet it is a rectangular piece cut from sheet foam about the exact size of the duct run.

[Fulltimer50]

https://www.amazon.com/Camco-Insulat...vent+insulator

[Hooligan2]

On the Siesta Sprinter, I added 2 new vents to the AC ducts in the cabin, just aft of the skylight. Good increase in cooling there.
The AC at that seam transitions from the roof ducts to ineffective small round tubing to get to the vents over the bunk.

[Lt Keefer]

I like the idea of the extra vents, may try that. Sorry about the lack of pictures, I don't think to photograph repairs or upgrades as I do them.

[Bob Denman]

Originally Posted by Lt Keefer

I like the idea of the extra vents, may try that. Sorry about the lack of pictures, I don't think to photograph repairs or upgrades as I do them.

I can understand that: I usually don't like to see photographic evidence of the stuff that I manage to bugger-up!

(NOT that I'm saying that you're as ham-fisted as me... )

[JamieGeek]

I post photographic evidence for my upgrades (and/or downgrades) good, bad, and ugly!

Sent from my SM-N950U using Thor RV Forum mobile app

[lildel]

Very nice & great idea because the vents up near the cab are essentially worthless. How did you know where to go into the ceiling?

[Hooligan2]

Remember it's a 2016 - The ac ducts in the styrfoam ceiling are parallel and run the full length of the ceiling. (up to that seam) I measured at the rear vents to get the spacing. Also by removing that light in front of the microwave I could see inside the full duct. Measure several times & cut once.
My dealer cut the holes, a good hole saw is important.

[lildel]

Originally Posted by Hooligan2

On the Siesta Sprinter, I added 2 new vents to the AC ducts in the cabin, just aft of the skylight. Good increase in cooling there.
The AC at that seam transitions from the roof ducts to ineffective small round tubing to get to the vents over the bunk.

Thanks, ours is a 2016 also , Siesta 24ST, your photo looks like our layout!

[asro8042]

Thanks for the excellent idea. We have a 2017 Citation Sprinter and the AC unit is a bit more forward but I think there is enough room to add to more vents into the duct work. Did you notice the airflow decrease to the over bunk vents after installing these?
I've done a lot of work trying to get those to blow more air. The problem is the flex tubing was leaking and the AC blower box was leaking so I HVAC taped the entire inside of the blower box. I also had gaps where the duct work connected to the blower box and air was blowing into the ceiling there and where the transition is to the flex tubing which goes to the bunk vents. I foamed and taped the gaps which helped. I think part of the issue with the over bunk vents is that the flex tubing is larger in diameter than the normal ducting so you loose a lot of air pressure. Also, the flex tube termination boxes over the bunk are large in volume so I cut and taped flashing and installed it in those boxes to reduce the volume and increase air pressure. About doubled the flow out of the front boxes. This could also be done with cut foam.

[nosticks]

Just completed the block off of the end vent runs. I have the a/c running out in the driveway now and I agree the air flow is a serious improvement. I have two vents over the front bunk which are never opened, so I blocked air from the next set back from getting to them.

I also took the time to clean out a ton of debris from the vent runs including pieces of Styrofoam and sawdust. I fished a small electrical tape from vent to vent and pulled a piece of mason twine with a dust cloth attached to the end, then vacuumed the cloth clean for the next run. Not so to improve any air flow, it's just that all that junk makes for dust and with my allergies, who need it.

[Lusitan]

I also have a 2016 Siesta 24ST and it came with 2 vents at the same exact location. Wonder if Thor forgot about your vents...

[Hooligan2]

After I did my vents I saw a few posts were Thor had installed additional vents as warranty for lack of cooling over the bunk area. Did not know it was also on production units.
My unit was ordered in April as a 2015, came out in June 2015 as one of the 1st 2016 models.

[Lusitan]

Originally Posted by Hooligan2

After I did my vents I saw a few posts were Thor had installed additional vents as warranty for lack of cooling over the bunk area. Did not know it was also on production units.
My unit was ordered in April as a 2015, came out in June 2015 as one of the 1st 2016 models.

Purchased my unit in April 2016. I imagine Thor reacted to owner's and dealership feedback and started added the vent modification. Any major issues so far with your 24ST?

[Hooligan2]

Originally Posted by Lusitan

Purchased my unit in April 2016. I imagine Thor reacted to owner's and dealership feedback and started added the vent modification. Any major issues so far with your 24ST?

I've been very fortunate, few problems and good relationship with my dealer and Thor. Just at 3 years and 34000 miles. I travel about 1 week each month, Florida, Carolinas, Tennessee to Louisianna.
I think RV's are like people, "If they rest they rust".

On the chassis I have had 2 wheel sensors fail at different times, , replaced under warranty.

[asro8042]

So I was able to add two vents to the ceiling in my 2017 Citation 24SR. Nice improvement in airflow with the air dump closed. While I had the holes open, I aluminum taped all the gaps and air leaks I could see. I also tool out the overhead lights near the new vents and could see where the manufacturer just punched holes in the styrofoam ducting to run wires. Air would leak into the ceiling so I taped these two. Then took out all the rest of the lights in the ceiling and found many places where these holes where. Plugged them up and now have excellent air flow. Thanks to Holligan for the idea....

[Lusitan]

Originally Posted by Hooligan2

On the Siesta Sprinter, I added 2 new vents to the AC ducts in the cabin, just aft of the skylight. Good increase in cooling there.
The AC at that seam transitions from the roof ducts to ineffective small round tubing to get to the vents over the bunk.

Based on Hooligan2's information, yesterday I completely blocked the airflow to the vents over the bunk since I only use that space to store all kinds of stuff. There is now big difference in cold airflow coming out of the ducts over the main cabin area.

This modification together with a cab separator curtain my wife and made, makes a huge difference cooling down the coach. The curtain has a dual purpose; when on the road, it retains the cold air from the chassis AC in the cab area. When parked, it keeps the cold air from the coach's AC from moving forward to the hot cab area. We used material from a set of Blackout Energy-Efficient thermal back curtains from Walmart to make the separator. Used snap fasteners to attach it to the top and sides, a large zipper in the center to allow passage, and some fishing sinker lead weight to keep the curtain taut. The idea came from an article I found in another forum a while back. Used the attached photo as a visual guide.