AC Window Unit Install

[Faulkster]

Mind you…this is nowhere near finished, but wanted to create a new thread to keep track of all I’ve found and my experiences.

First of all my 5th-wheel had a *single* Coleman Mach roof-mount ducted unit when I purchased from my mother-in-law. This poor thing NEVER cooled the camper down to a decent level during the summer. Best it could do was maybe 80 degrees. I live in South Louisiana, so this is a big deal.

My first major purchase for the camper with a new 13,500BTU Coleman Mach III unit and then I installed it in the bedroom area. I then removed the ducting from the living room A/C and installed a roof-mount control. This worked decently well and was OK until the living room A/C died (compressor locked up). Thank God for the cool front that came through!

I’ve heard multiple stories of people installing window units in their campers with great success, so thought I’d give it a shot. I know I can’t travel this way, but my 5th-wheel is set up permanent on my property.

Honestly, I bought the Mach III new on sale for $580 and it has seriously disappointed me with its’ performance. The $75 5000BTU window unit I temporarily stuck in my slide-out window works SO much better. Shameful really…these roof-units at 13,5000BTU should make icicles!

I traded the 5000BTU unit to my dad for his 8000BTU because I have my kids over often and campers are not well-insulated. By my calculations, I needed 7800BTU. 🙂

What I did was to remove (1) of the solid slide-out windows and cut out a piece of 3/4″ plywood to cover the entire opening. I then cut out a hole in the plywood to tightly fit the window unit in to. I am in the process of making wood trim pieces for the outside and inside so it doesn’t look so crappy. Hehe. I can actually close the slide with the plywood in place when I remove the window unit!

• This topic was modified 9 years, 3 months ago by Faulkster.
• This topic was modified 9 years, 3 months ago by Faulkster.
• This topic was modified 9 years, 2 months ago by Pippi.

[Roger]

Quite ingenious!

[Faulkster]

Thank you sir, oil-based primer and top-coat paint going on today!

I was going to prime/paint before installation but it was 10:30pm when I finished.

[Pippi]

Interesting the lower BTU units work better than the bigger ones. I hear you though, 80 is a good ‘cool’ temp with them. I know the 50 amp system coaches can run two roof units which helps significantly.

I’m wondering if you had made sure the Coleman units were cleaned inside, filters and coils. After having done my video about getting cooler temps by just cleaning the filters, a bunch of folks chimed in to say cleaning the coils and inside the indoor cover, as well, can make a huge difference in the cooler temps it can put out.

Kudos on the new installation! It might be worth putting a layer of thin insulation on the plywood, whether it be reflectix material or even a thinner rigid insulation. You can get small pieces at your local big name hardware store for only a couple bucks.

Thanks for sharing!

• This reply was modified 9 years, 2 months ago by Pippi.

[Faulkster]

Thanks Pippi!

I sure did clean my A/C units after watching your video a couple months ago. It did not help, but ultimately the living room A/C was dying and this was a part of why it didn’t cool well at all.

The plan is to insulate the top of the 5th-wheel and the tops of the slides the way you did yours. How is that working by the way?

I have been checking cost for a company to come and build a cover for my 5th-wheel, but that is out of my budget. Hehe

So far, turning off the roof unit and installing the window unit has reduced my electricity bill considerably.

[Author]

Posts