Building a Micro-Split AC System

[DCH109]

While I thought you were a madman, now I am wondering.
After looking at small systems out there most are $$$, mounted to the roof (not ideal for clearance) or not great quality.

I happen to have a spare unit I bought and never used, I may have to copy you here as this would be perfect for my Camper build.

 

[luthj]

While I thought you were a madman, now I am wondering.
After looking at small systems out there most are $$$, mounted to the roof (not ideal for clearance) or not great quality.

I happen to have a spare unit I bought and never used, I may have to copy you here as this would be perfect for my Camper build.

If you have the space, one of these slightly larger 8kBTU units would be an easier donor. Its already partially split, with separate evap and condenser fans/motors.

Amazon.com: Midea U Inverter Window Air Conditioner 8,000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation,Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Home & Kitchen

Buy Midea U Inverter Window Air Conditioner 8, 000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation, Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Window - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[DCH109]

If you have the space, one of these slightly larger 8kBTU units would be an easier donor. Its already partially split, with separate evap and condenser fans/motors.

Amazon.com: Midea U Inverter Window Air Conditioner 8,000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation,Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Home & Kitchen

Buy Midea U Inverter Window Air Conditioner 8, 000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation, Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Window - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

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Oh I will have the space as I am building this from scratch and will incorporate AC into it. It is hot on the east coast in the summer. Currently 98* feels like 105*.
I will check it out thanks for the link!

 

[Hillbilly Heaven]

If you have the space, one of these slightly larger 8kBTU units would be an easier donor. Its already partially split, with separate evap and condenser fans/motors.

Amazon.com: Midea U Inverter Window Air Conditioner 8,000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation,Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Home & Kitchen

Buy Midea U Inverter Window Air Conditioner 8, 000BTU, U-Shaped AC with Open Window Flexibility, Robust Installation, Extreme Quiet, 35% Energy Saving, Smart Control, Alexa, Remote, Bracket Included: Window - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

View attachment 600033

Oh I like that. It is a new product and delivery has been sketchy. But they are managing to get them shipped out. The inverter tech is a big power saver. Looks like most of the reviews are about how difficult installation is and getting window to seal, not a problem if splitting the unit. Wished I had seen this yesterday. I had to buy another window AC for our temporary housing situation.

 

[luthj]

Got some of the AC parts. Here are the low loss disconnects.

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It's coming together.
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Excuse the hack job, but I have deadlines to meet. I did some math, and added a bit more airflow with some louvers. I also added deflectors to the sides, to help reduce recirculation of hot air.

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[RVflyfish]

Man, what a cool project. Again no pun intended. I’m constantly amazed at the knowledge, skills and ingenuity on this forum. Way to go Luthj!

 

[luthj]

I just got the electrical connectors, so I am ready to finish up the wiring and paint everything. After that I just need to bolt everything in and run a bunch of wire and copper lines. I anticipate the copper lines may be the hardest part. I could go with flex lines, but they area pricey, so I want to avoid if possible.

 

[luthj]

Getting pretty close. Still waiting on some small ID pipe insulation.

I opted to hit all the copper lines with some cold galvanizing spray. Its 70% zinc, and should extend their life under a vehicle. I glued a cap over the unused motor end/bearing. I also glued a seal to the output side of the condenser fan. The motor still has a drain hole at the bottom, but having these two seals should reduce the risk of crap getting washed into the bearings. The starter cap is mounted and the harness complete. Since the fan condenser fan only needs one speed (high), and will always run with the compressor, I just ran three wires and a waterproof connector for easy removal.






I got the fittings soldered onto the evap lines. They clamp to tabs on the pan, and I put rubber for chafe and heat transfer resistance.



Wiring is done on the inside unit as well I used 2 of the same waterproof 3 wire connectors here. The small black box is the 6uF cap for the evap fan.




Got the evap unit mostly together. Should get it completed tomorrow. I also set the rivnuts for the interior/exterior mountings, and got the shelf ready to go in.

IMG_20200727_165553921 by J Luth, on Flickr


Major tasks left are running the refrigerant lines, and the power wires. Followed by an evac and charge. Well, a leak test first with vacuum to make sure I didn't screw it up too bad.

 

[tanuki.himself]

i'd be interested to know what each half of the finsihed thing weighs when filled - i know the compressor is a big chunk of the weight...

 

[luthj]

i'd be interested to know what each half of the finsihed thing weighs when filled - i know the compressor is a big chunk of the weight...

Indoor unit is 15lbs, I will weight the outdoor unit when its assembled. I will guess its about 30lbs.


Sooooon.

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[luthj]

The outdoor unit is 33.5lbs.

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Since the unit is right behind the hitch receiver, I need to make sure my inserts aren't too long, and will crush the condenser. I could weld a cap on the receiver tube as well, and I may do that when I drop it for a coat of paint later on.

Working on the lines. Going a bit better than I expected. I should have swapped the high/low line position on the evap. Not a big deal, but the lines needed to cross over on the vertical run.

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[luthj]

Got it closed up and vacuumed down. I will let it sit for a few hours to see if it leaks at all. I still need to secure the lines, seal the floor hole, and wrap some insulation on the couplings. Wiring is all good as well. Hoping to find someone next week who can charge it, but I haven't started calling around yet.

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[dreadlocks]

This is the coolest thing happening on expo portal right now..

 

[luthj]

This is the coolest thing happening on expo portal right now..

Very Punny indeed.

Thinking about the semi-split window unit that was posted previously. Using that unit, I could have knocked this project out in a quarter the time. Solder some lines, splice some wires, make some brackets, etc. Of course its a bit too big for my mounting locations, but not a bad idea for others to consider.

 

[roving1]

The workmanship skill and thought process as always is impressive. I just don't get how one drive on a silty or muddy road doesn't ruin this thing though.