DIY air conditioner question...

[Ruthless53]

New member here and have been really enjoying the reading and all the great ideas. Been working to get my garage up to workable standards with shelves I'm currently building so I can get rid of my big metal shelves and gain some floor space for a couple benches I'm going to build next.

I've been playing with air conditioners for my garage. We just had our 2nd child so budget has not allowed for a mini split. So for now I've built a kind of closed system air conditioner that I built using a small cooler with a water/antifreeze mix pumped via a fountain pump through 70 feet of copper tube coiled in another bigger cooler filled with dry ice. From there it's pumped through a transmission cooler I got at a salvage yard for 15 bucks and has 2 floor fans pushing air through it with water returning to the small cooler. It works great and the dry ice lasts quite awhile and cools the garage (standard 2 car with insulation and insulated door) down about 15 degrees or so. But I have an opportunity and an idea and I need to know from people smarter than me if it would work. 1st here is the current cooler. Pretty proud of it. Built out of scrap stuff and in a couple hours. Wood work was rushed and not pretty but it's air tight. Also it's on a cart I made a put casters on and also only uses one plug.

 

[Ruthless53]

So I have a friend that refurbs large CO2 tanks. MHD has a lot of single phase low temp cooling systems that cool the co2 inside the tanks using a coil system. The unit I'm thinking of using came off a 5k gallon co2 tank. I can get several of these working units free and get everything I would need. Basically all parts outside of the tank. Coper pipe, expansion joint, filter ect.

 

[Ruthless53]

My though is to hook it up the same way as the coil system in the tank except use an air conditioner evaporator similar to this instead of the coils.

Sorry for multiple posts but I can only post one picture at a time from my iPad.

 

[Ruthless53]

I would then build an enclosure and use either a Vornado commercial fan I have to push air through the evaporative coil. The condenser unit would be outside on a small pad and the inside part would be 2 pipes running through the wall with the evap/fan being inside similar to this but with an enclosure and better fan and evaporator.


Basically in my mind it's the same principle as my current diy ac but the refrigeration unit gets considerably colder and should cool better. What would be my problems with this concept? All work would be done by his employees that install these in the co2 tanks. I believe this is a similar set up to the way a walk in refrigerator would be except using stuff I can get free. The unit I'm thinking of using is a 1hp single phase unit.

 

[nine4gmc]

in for info

 

[pseudorealityx]

In a garage application, it sounds like you'll freeze up your evaporator coil. A refrigeration unit is designed around very dry air, not a garage. Too much moisture + very cold coil = ice.

 

[Mike007]

Just a thought, wouldn't it be a lot easier, cheaper and more effective to pick up a used window/wall AC unit on Craigslist then attempting to reinvent the wheel?

 

[Mike007]

Just a thought, wouldn't it be a lot easier, cheaper and more effective to pick up a used window/wall AC unit on Craigslist then attempting to reinvent the wheel?

And the window/wall unit can probably be purchased new for the same price as a new A coil.

 

[mayday0017]

Was kinda thinking the same about a window unit... Figured he could pick one up for $50 and it would work better and be cheaper in the long run then any other possible home built setup....

I see well over $50 ******* in the first rig with 2 ice chests, 2 fans, a coil, and the copper line....

Best of luck on making a system as I figure the project is 1/2 the fun and that is probably why you are doing it. But I have to agree a window unit would be the way to go if the goal is really to cool the place some on a budget.

 

[Ruthless53]

Was kinda thinking the same about a window unit... Figured he could pick one up for $50 and it would work better and be cheaper in the long run then any other possible home built setup....

I see well over $50 ******* in the first rig with 2 ice chests, 2 fans, a coil, and the copper line....

Best of luck on making a system as I figure the project is 1/2 the fun and that is probably why you are doing it. But I have to agree a window unit would be the way to go if the goal is really to cool the place some on a budget.

Yes the reengineering is why I would want to do it. Figuring out other uses for things or better design is something I've come to really enjoy. Actually why I'm getting a couple of these units free is because I'm helping him to design something using this same unit to chill his pool water in the hot Texas summer! Yes a window unit would be a whole lot easier other than the fact I have no window so I would either have to cut through the in bricked area or cut through the man door. A couple hundred bucks as I go is no big deal. 1k -1500 would be a tough swing right now and by the time that became doable summer would nearly be over. Did I mention having a baby is stupid expensive now a days! 5 days in NICU=$50,000 hospital bill on top of the $10k paid ahead of time. After receiving that bill it was quickly decided 2 kids would be plenty!!

I've found a evaporative coil like the one pictured for $50 here locally. All the copper tubing I can get free. Only other thing I would have to pay for would be the switch if I want to hard wire it in. I had all the materials for the cooler I built already except for the trans cooler so that is actually the only hard cost I have in it.

The biggest concern for me was frost. Would it frost because of it being a low temp coil vs a med temp coil? I've been in some humid walk in coolers and can't rationalize in my head why it would freeze in my application but not a walk in freezer? That's why I came for answers from people that know a whole lot more than me.

 

[pseudorealityx]

The biggest concern for me was frost. Would it frost because of it being a low temp coil vs a med temp coil? I've been in some humid walk in coolers and can't rationalize in my head why it would freeze in my application but not a walk in freezer? That's why I came for answers from people that know a whole lot more than me.

Because a very 'humid' walk-in cooler has the same amount of moisture in the air as 'dry' garage at 75 degrees.

 

[cagullett1]

Same boat.. my wife is pregnant with our second kid, bricked in 2 car garage with no window. I'm about to order this mini split for $670. Best deal I could find and the only reasonable way to cool the garage during Texas summer. More than I wanted to spend, but its the best investment I could find.

http://www.amazon.com/gp/product/B0095V0OYM/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=ATVPDKIKX0DER

 

[Ruthless53]

I have been watching Craigslist for awhile looking for a good deal on something that I could use out there but never saw anything I considered a really good deal until yesterday. I picked up a MovinCool Classic 10 for $300 bucks. Came with the original packing slip from the company that bought it in 2010. It is missing a know (pliers work for now) and has a couple scratches but works beautifully and even with venting under my garage door opened a couple feet cooled my garage down considerably yesterday afternoon. This thing has a 12 freaking inch exhaust hose so Im going to go through the man door since I never use it anyway and just replace it when I move vs going through the wall. Also probably going to build a shelf to get it up off the ground so I don't have to worry about moving it to sweep or anything.



http://www.mobileair.com/portable-air-conditioners/movincool-classic-10