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Simeonx1
08-02-2012, 12:19 PM
So i thought i would make an Air conditioner from scratch.

The basic system is rectangle box , im using an old esky

Ive put separated The rectangle into to halfs . one for evap and one for condenser .

Ive made copper coils from 1/4 inch pipe . a few meters long .

Im going to use an old freezer compressor to pump the gas around.

The idea of the system is to make to water almost freeze then have a fan blowing out the cold air. The comp would be running as much as a fridge does.

And for the condenser have water slowly flowing through it to take away the heat. A drip every 2 seconds coming out and room temp water coming in from a new bucket.

My question is . Would i be able to use my gauges as a metering device to restrict the refrigerant until i figure out the perfect cap tube ?
Just use the superheat of the evap and close of the gauges until its good?

And i will also need an accumulator after the evap to help hold the charge when the system is not running ?

Also how much gas should i use , i cant find any info in my books that lets me know how much gas i need for the size of the coils .

Ive been working for 7 years , installing splits and vrv welding all day hasent really tought me these things

monkey spanners
08-02-2012, 03:33 PM
I used an old danfoss hand valve for fun projects, was a bit hit and miss, a needle valve would be better if you can find one rated for refrigerant.

Brian_UK
08-02-2012, 06:55 PM
Also try and get some data on the compressor. Small ones often have a 'critical charge' which is the maximum refrigerant allowed in the compressor shell, this might give you a start point.

install monkey
08-02-2012, 08:31 PM
instead of all that messing about- why not use a chest freezer as all the components are size correctly and charge is correct too- fill it with water - then it is already insulated- then mount an extract fan with a grille at the opposite side of the chest to draw cold air accross the pond of cold water-also u can dunc for beers too- just change the stat for a fridge type- cycles at 2-7 deg
can u tell that i used to dismantle things as a kid!!! haha


So i thought i would make an Air conditioner from scratch.

The basic system is rectangle box , im using an old esky

Ive put separated The rectangle into to halfs . one for evap and one for condenser .

Ive made copper coils from 1/4 inch pipe . a few meters long .

Im going to use an old freezer compressor to pump the gas around.

The idea of the system is to make to water almost freeze then have a fan blowing out the cold air. The comp would be running as much as a fridge does.

And for the condenser have water slowly flowing through it to take away the heat. A drip every 2 seconds coming out and room temp water coming in from a new bucket.

My question is . Would i be able to use my gauges as a metering device to restrict the refrigerant until i figure out the perfect cap tube ?
Just use the superheat of the evap and close of the gauges until its good?

And i will also need an accumulator after the evap to help hold the charge when the system is not running ?

Also how much gas should i use , i cant find any info in my books that lets me know how much gas i need for the size of the coils .

Ive been working for 7 years , installing splits and vrv welding all day hasent really tought me these things

Simeonx1
09-02-2012, 08:26 AM
Yeah i knew about the hand value thing . thought two hand vavles on my gauges would do . going to be hard to get purfect .
I did think of the freezer part . But was thinking its to hard to get it water tight . and if you have it on its side the comp is on its side. Mybe i can change the comp to site on something different .
Also i was hoping my system would get the water down to temp faster than the freezer does becuase its smaller with the same comp . So i can run it for 10mins and get enough cold water for 30min of use.

Thanks for your help .

edit .
ooo a chest freezer yeah that would hold water good .
Reason why i wouldnt use it. Its cheating and wouldnt be as fun to do just the fan part of things.

Also i figured if the condenser was in the same room as the cool air blowing out , Then IT WOULD BE CRAP .
Might aswell pitch a tent over a open fridge door .

Any one who can make a homemade air con please post some pics :P