Best Way To Add A/C to a older trailer?

ajriding wrote:
The best is the roof unit. There is already a 14.5 inch square hole on the roof and it is likely, most likely, intended to support the 95 lbs or so weight of an AC unit. You can install this yourself if you posses the most basic of skills. It is not hard to do, and these skills you could even learn by watching a few vids.

Depending on the generator size you might want to consider the size AC unit you need. The typical one is a 13,500 BTU size. For small generators of around 2,000 or 2,200 watts you will need a smaller AC unit of about 9,000 BTU. For a 20 foot trailer this might be enough. Keep in mind that as altitude increases the generator power decreases and the AC will be harder to start, so if you want to camp above 5,000 or so then research what gen can run what AC at altitude. Either size will be expensive compared to a window unit.

Installing a window unit is cheap bc they are $99 but would require a lot of modifications to make it work depending where you are able to install it, preferably the back wall.

The mini-split units are nice, yet cost more than a window unit, but will have challenges to install it also. They tend to be more efficient, so a small generator can be used, and I have seen one guy run a split off a roof-full of solar panels, something you can't do with the roof top ACs.

I suggest getting a roof AC unit.

Roof unit is not the "best", it is the EASIEST.

Wall/Window units are much more efficient, because they "splash" the A/C condensate water over the outside cools. RV roof A/Cs do not splash the condensate, they also sit on top of the HOTTEST part of a RV, THE ROOF.

Had a 1980s 20ft TT which when we bought it had no A/C unit, bought a window unit, picked the rear back closet and cut a window A/C size hole to the outside in the bottom of the closet.

Made a aluminum splash pan to go under the unit, cut the bottom of closet door off. A/C rested on some rails I made with 2x2s and only the rear coils of the A/C showed. Disguised that with a metal RV fridge access panel and the side of the trailer I added a intake vent for the A/C.

We were able to use a 11K BTU wall A/C and it would turn the 20ft trailer into a meat freezer..

My current TT, a 26ft one I went with a 10K wall unit in the rear and our dedicated walled off master bedroom in the front has it's own 6.5K BTU unit.. Both are hidden in similar fashion as to our 20ft one was..

Both Window A/C units are quieter than any roof A/C unit I have heard, they make Window units much quieter now days than they used to be.

Cost for both A/C units was $350 vs a roof A/C at $800 plus..

Very comfortable and we even get a REMOTE CONTROL which is real handy..

Not gonna get a remote control with a roof A/C either..

If one is handy, has the vision, has the talent, one CAN adapt..

Most rigs are wired for a roof air. The wire quite often is located behind the plastic decorative frame. The wire is coiled behind breaker panel.

Could find an AC unit at local salvage yard.

Easiest is to take it to a dealer and replace one of the 14" roof vents with an air conditioner.
Find a campground with electric power and skip the generator.

The best is the roof unit. There is already a 14.5 inch square hole on the roof and it is likely, most likely, intended to support the 95 lbs or so weight of an AC unit. You can install this yourself if you posses the most basic of skills. It is not hard to do, and these skills you could even learn by watching a few vids.

Depending on the generator size you might want to consider the size AC unit you need. The typical one is a 13,500 BTU size. For small generators of around 2,000 or 2,200 watts you will need a smaller AC unit of about 9,000 BTU. For a 20 foot trailer this might be enough. Keep in mind that as altitude increases the generator power decreases and the AC will be harder to start, so if you want to camp above 5,000 or so then research what gen can run what AC at altitude. Either size will be expensive compared to a window unit.

Installing a window unit is cheap bc they are $99 but would require a lot of modifications to make it work depending where you are able to install it, preferably the back wall.

The mini-split units are nice, yet cost more than a window unit, but will have challenges to install it also. They tend to be more efficient, so a small generator can be used, and I have seen one guy run a split off a roof-full of solar panels, something you can't do with the roof top ACs.

I suggest getting a roof AC unit.

Trailers in that length range won’t have a storage bay fora generator. Will your sister be able to move a 45 pound inverter generator from the TV to the ground or table? Change the oil? Etc.

you mentioned two frequent methods. A third is using a mini split system. Mini splits generally use less power, but are more expensive than a small window unit AC. They are also quieter and more efficient.
Here are several in the appropriate size range of 9000 btu. You would want a 115/120 volt model.
Mini splits

Check you tube there are quite a few video's folks mounting them on trailers.