Second air conditioner

[Jenrnfnp]

We have a Sabre 32RCTS with a 15,500 BTU a/c in the living area. On really hot days it does not cool down the bedroom in the front even if we close the vent in the back. It is wired and set up for a second a/c in the bedroom. Our question is what size a/c is appropriate?

[ret2006]

Originally Posted by Jenrnfnp

We have a Sabre 32RCTS with a 15,500 BTU a/c in the living area. On really hot days it does not cool down the bedroom in the front even if we close the vent in the back. It is wired and set up for a second a/c in the bedroom. Our question is what size a/c is appropriate?

13,500 BTU in the bedroom is what my 2012 Sabre 31 RETS came with. You can come close to using the bedroom to cool your beer when it is on high in 100 degree weather. The living area 15,000 BTU unit keeps the main area comfortable, not cold, in 100 degree heat but it runs continuously. With all the windows that is about all you can expect. I put some Reflectix on some of the windows facing the afternoon sun. That helps a lot. I am sure glad my dealer orders all his Sabres with the second air conditioner. Not a Sabre on his lot that does not have two A/Cs.

[slide5r4fun]

We have a 32RCTS and live in Texas so we had a 2nd a/c installed as part of our purchase . If memory serves me correctly it's a 13,500 BTU and makes all the difference in the world. It still takes a while to cool the rig down when you pull in to camp in the early afternoon in 90+ degree heat but it will get the job done. You will need 50 amp service to run your 2nd a/c, but when the weather cools you can go back down to 30 amp service and use the primary a/c only. Get yourself a 50 amp to 30 amp "pigtail" and you will be set.

[QCCowboy]

I can't tell you too much on what size second air conditioner to put in, but looking at other posts it looks like a 13.5k is recommended. One thing I would recommend before you make the investment in a second air conditioner though is that you go through all of your vents and check for "gaps" between the vent shaft and the vents themselves. I would also recommend pulling down the air conditioner cover from the inside and look at both the right and the left hand side shafts (when the quick cool vent is closed the air is forced through them.) Check to make sure that there are no gaps or holes around the shafts themselves.

I had a similar problem to yours with the camper not cooling down and was going to invest in a second AC unit, unfortunately my Sabre was not wired up for a second AC from the factory so it would have been a little more costly. When I pulled all of the vents and the AC cover I found multiple areas where the cold air from the AC unit was essentially escaping into the area between the vent and the roof. The side that forced air up to the living room and front bunkhouse actually had about a 1/2 inch to 1 inch gap nearly all the way around it. Closed them all up with some aluminum tape and was ready to give it a whirl.

Just got back from a trip to the Lake of the Ozarks where it was 100+ every day (no shade on the camper). Amazing what the difference in air flow was and the inside of the camper was a comfortable 78-80 degrees, which I never would have achieved before doing this (I also have a 15k AC unit). Total cost for me, about $6.00 in tape and my time.

[SimchaSabre]

QCCowBoy,
Can u post pics..I'm having trouble visuallizing the gaps you speak of.


Thanks

[QCCowboy]

I will see about taking some pics this evening. I wont be able to show you the gaps as I have sealed them up, however I will try to outline the areas where they used to exist.

[QCCowboy]

Sorry it took a while to get these, had a few things going on this evening. I will admit I am not an expert, but here are the steps and some pictures of what I did. The difference after I was done was night and day (made my wife and kids very happy!)

Here are some of the pictures that I captured (going to have to split this into a couple of posts):

First start off with the air vent:

You need to remove the cover:

Once you have the cover off you will most likely see some tape already:

You will actually need to feel around the inside of the vent for small gaps or holes where taping was missed. When you are done you should not have any gaps, took me quite a bit of tape as there were some big holes.

To put the vents back on, just do the reverse of taking them off, the louvers in the vents can be a bit of a pain at times and I had a couple that would actually continually shut from the force of the air. I just put some of that tacky putty used for handing my kids artwork on the walls in between the ends of the louvers and all is well!

Repeat for each air vent in your camper.

[QCCowboy]

Now on the the AC unit itself.
You need to remove the filter first then there will be a couple of plugs that cover two screws. Remove these. In total on my unit there were six screws.

Once you have them off, here are the areas that you want to focus in on:

Looking at the picture above, the bottom part is where the air is forced into the vents that feed into the cabin when the quick cool is closed. The top part is the return vent from the cabin where the air is recycled. In the picture below I tried to outline where the gaps existed (as you can see they are now taped up, and yeah I probably went a bit crazy with the tape

There are two different air shafts in my unit, one on the right and one on the left (these would be found where the air is forced into the cabin.) One feeds the back of the camper and the other the front. You need to check them both out.

[QCCowboy]

Some other pics:





You also want to check all of the corners for any holes (don't want any of the cold air escaping)

[QCCowboy]

Probably also want to peel back the foam tape and look behind it as well as there are corners in which air can pass through. I just taped these up.



Last but not least, do a double check around all of the potential openings.


Took a little bit of time, but not really that difficult and well worth it!

[fkent1]

Now that is a great idea and place to check. Thanks.

[SimchaSabre]

QCCowboy...Thanks for the pics and the great report on your fix. We have diffrent vents in our 2013 Fith wheel but the ac unit looks the same.

I'll be out there this weekend with my duct tape and silicone Sealant.

[QCCowboy]

Glad to help. Make sure you use foil tape and not standard duct tape (found at any hardware store and even WM.) It is just as adhesive however it will hold up much better in the moisture that the AC creates than duct tape.

[jsk]

A question about adding a 2nd ac = do you tie it in to your current ductwork or not? Is the advantage of this noise reduction?

[QCCowboy]

While I don't have a second AC unit , I would assume that it would tap into the existing duct work. Having to add new duct work would be a real pain. The only other way i can think of would be if a second AC unit only forced air out of the quick cool vent.

Either way the intent would be greater cooling power and more efficiency when cooling (allowing a camper to cool down quicker or different cooling zones.) Not necessarily less noise.

Now with a second AC comes the requirement of 50 amp wiring and pedestal service if you want to run both. This what you were asking?

[slide5r4fun]

Our 2012 RCTS came pre-wired and ducted for the 2nd a/c. I would imagine that all Sabre units are "prepped" this way. The advantage to the 2nd a/c is increased airflow and cooling power. The disadvantage is noise, particularly in the bedroom. Also, it will require 50 amp service to run the 2nd a/c whereas you can get by on 30 amp service when using the primary unit alone. To eleminate the noise issue, you could always turn the thermostat off on the bedroom unit at night.

[MartyI]

My AC has never been that great either. I always blamed it on all the windows, and lack of insulation in the slide roofs. I added a portable AC in the living room, and that helped alot. On a recent trip I pulled the AC filter cover off and found that the baffle between the air return side and the cold output side had come loose and fallen down! So the AC was just pulling some of the cold air back into the input side. No wonder it wasn't cooling down the trailer very well. Decided to check all the output vents too, as around some of them the ceiling was cold, but not much air was coming out. The taping around the output vents was poorly done, as there were gaps and holes that the air was escaping from. Also the AC made a lot of noise in the living room. I figured out the rear two mounting bolts had backed off about an inch. I tightened those up, and it runs much quieter now. I haven't gotten to test out the new tape job yet, but I'm sure it should cool down much better next summer!

[okietom]

I have a 2012 34RLQS and it is wired for a second A/C that I plan on installing next spring. It does not connect to the existing duct work, I have not seen one that does.