Let's Convert an A/C to a Chiller...

OK, I have reservoir issues....

I have my reservoir in the basement setting on the concrete ground and my temp goes from upper 60s to upper 70s
in a 18hr day's time...

I do not have the funds to spend $500 on a chiller...
So I'm going to make one for around $130 that will work just as good as a 1/4hp chiller....


Parts:
1 - 3/8" x 25' Stainless Steel Wort Chiller = $44.00 ($13.00 to ship to my address)
(this Stainless Steel Wort Chiller comes with 20' of hose and a garden hose fitting for the 3/8" hose, so it's ready to go)

1 - 396gph pump = $20 (I used a spare, but I'm sure you could just use like a 185gph $12 pump)

1 - Old 5,000 BTU Analog A/C unit = $20 (I bought from a garage sale)

1 - old plastic tool box - $10

I'm also adding some duct work on the back of the unit to get rid of the condenser's heat into my central exhaust system... The duct work and tape is maybe $20...


So we're setting just under $130 for this conversion...



NOW, you do not have to spend the extra money on the Wart Chiller Coils, you can just get a 25' of 1/2 or 3/8" tubing.
The 3/8" tubing is $34.00 and same shipping cost, so I spent the extra $10 to get it coiled, the hose, and fittings..
IMO, it's worth the extra $10.00.....




OK, I KNOW it's going to be asked as 99.9% of conversions just hang the A/C's evaporator right in the reservoir....
ALL A/C (new and old) evaporator coils contain copper which we cannot use in our reservoirs with nutrients..

It's already been proven we MUST use at least a 304 Stainless Steel, because copper leaches into the nutrient.
Another reason is this A/C is old and the evaporator coils are NASTY, which I do not want in my res...
Lastly, if this were a new unit, they spray the evaporator coils with a corrosive inhibitor, again not good in the res..

So IMO, the people just hanging the evaporator right in the reservoir are not right in the head... LOL



OK, this is a REAL simple conversion....



Started by finding an old A/C window A/C unit...
http://forum.grasscity.com/attachment.php?attachmentid=906992&stc=1&d=1340319917


http://forum.grasscity.com/attachment.php?attachmentid=906993&stc=1&d=1340319917



Then I pulled off the outer cover....
http://forum.grasscity.com/attachment.php?attachmentid=906996&stc=1&d=1340320080


http://forum.grasscity.com/attachment.php?attachmentid=906997&stc=1&d=1340320080


http://forum.grasscity.com/attachment.php?attachmentid=906998&stc=1&d=1340320080




As you can see, 99.9% of window A/C units have only 1 motor which run both the evaporator and condenser fans..
I removed the top fan shroud, then the motor which is a single shaft motor, and driving both fan blades...
http://forum.grasscity.com/attachment.php?attachmentid=907001&stc=1&d=1340320356


http://forum.grasscity.com/attachment.php?attachmentid=907005&stc=1&d=1340320650




I simply cut off the motor shaft which was driving the evaporator fan side..
Then I remounted the motor, condenser fan, and shroud back onto the A/C unit.
http://forum.grasscity.com/attachment.php?attachmentid=907003&stc=1&d=1340320578


http://forum.grasscity.com/attachment.php?attachmentid=907004&stc=1&d=1340320578



Now I needed to find a small reservoir and after a quick look around....
Perfect, an old plastic tool box...
http://forum.grasscity.com/attachment.php?attachmentid=907006&stc=1&d=1340320990



That's the conversion....
Next post I will get the pump in the reservoir, hooked to the Wort Chiller coil, and then fire it up to see if it works..

Edited by jakesterjammin, 21 June 2012 - 11:51 PM.

OK, on with the show...........


At this point we're pretty much done...
I could easily put the cover back on the A/C and hang it out the window...


But I have a central exhaust system setup, so I'm going to make some duct work and I can vent the Chiller's heat into
the exhaust system..



So where we left off, the conversion to the A/C is really done...
All we have to do now is take our fittings that came with the Wort Chiller coil, hook them up to the chiller..

I used a 1/2" garden hose repair fitting for the hose from the pump, which hooks right to the Wort Chiller hose's fitting..
http://forum.grasscity.com/attachment.php?attachmentid=907032&stc=1&d=1340321931



And after about 15 minutes, we're down at 43°F.......
http://forum.grasscity.com/attachment.php?attachmentid=907033&stc=1&d=1340322076



Now we have a working Chiller which will have NO PROBLEM chilling 50gal res in the most extreme temps...
http://forum.grasscity.com/attachment.php?attachmentid=907034&stc=1&d=1340322114




This also can be applied to smaller systems such as bubble buckets or rdwc systems...
You can also do a system like this but reversed and using only 2L pop bottles with frozen water....
If you want me to explain how, just ask....



Hope this helps someone....




EDIT:
Once I get the Chiller installed, I'll take more pics of it in action....

Edited by jakesterjammin, 21 June 2012 - 11:48 PM.

OK, this is round 2....

When I bought that old shitty A/C, the wife was like "you're going to do what with it??? " ........
So last night I Micky Moused it in, fired it up, and in 20 minutes drop the 40 gal res temp 10°...

Well the wife was like , "that's bad ass, can you do that with any A/C??" .....
Told her sure, but it should be Analog or have auto restart....



Well because this A/C looked like this.........
http://forum.grasscity.com/attachment.php?attachmentid=907513&stc=1&d=1340381010




She goes out this morning and what does she come back with??????
http://forum.grasscity.com/attachment.php?attachmentid=908186&stc=1&d=1340415264


http://forum.grasscity.com/attachment.php?attachmentid=908189&stc=1&d=1340415352



And says, do it again, with this one....



So here we go again.....



I used a Philips Screw Driver, a piece of sheet metal, some gloves, a hacksaw, some foil tape, and sheet metal snips...



I first took out all the outside screws and removed the cover, reviling the inside.....
http://forum.grasscity.com/attachment.php?attachmentid=908190&stc=1&d=1340415531



Then I removed a couple screws holding the controls, and laid them off to the side...
http://forum.grasscity.com/attachment.php?attachmentid=908191&stc=1&d=1340415616



The top Styrofoam comes right off, or may be taped to the bottom half.......
http://forum.grasscity.com/attachment.php?attachmentid=908192&stc=1&d=1340415790



At this point we need to remove the fan motor and again it's a dual shaft motor which drives both fans...
On this model the motor, fans, and fan shroud is all one piece and removed with 2 screws....
http://forum.grasscity.com/attachment.php?attachmentid=908196&stc=1&d=1340415916



Now the whole motor, fans, and fan shroud assembly lifts straight up and off....
http://forum.grasscity.com/attachment.php?attachmentid=908197&stc=1&d=1340415988



Now while holding the motor assembly, slide out the bottom Styrofoam piece, and then re-install the motor assembly..
http://forum.grasscity.com/attachment.php?attachmentid=908198&stc=1&d=1340416044



Now that dual shaft on the motor, we need to cut that off and I used a hacksaw which worked out great...
http://forum.grasscity.com/attachment.php?attachmentid=908208&stc=1&d=1340416329



SWEET!!!


At this point I slipped the old plastic tool box under the evaporator and this is what I had......
http://forum.grasscity.com/attachment.php?attachmentid=908215&stc=1&d=1340416521




To be continued......

Cool, let's continue......



I now wanted to modify the A/C's cover to fit the new Res on the front...
So I basically cut off the part of the cover which went around the evaporator and I used the sheet metal cutters for this...
http://forum.grasscity.com/attachment.php?attachmentid=908216&stc=1&d=1340416695



I want to separate the hot and cold side, so I can use spray foam to insulate the chiller's res...
http://forum.grasscity.com/attachment.php?attachmentid=908217&stc=1&d=1340416919



So I used a piece of sheet metal, bought at Home Depot for $3....
I bent it at the top and bottom, then used self tapping screws and secured the bottom...
http://forum.grasscity.com/attachment.php?attachmentid=908218&stc=1&d=1340417111



Now I simply installed the modified cover back on the A/C unit......
http://forum.grasscity.com/attachment.php?attachmentid=908222&stc=1&d=1340417373


http://forum.grasscity.com/attachment.php?attachmentid=908229&stc=1&d=1340417494



At this point, I run a few self tapping screws in the top and foil taped up the seams.....
http://forum.grasscity.com/attachment.php?attachmentid=908238&stc=1&d=1340417664



ALSO, in that pic above, notice the blue shit sprayed on the fins of the evaporator....
This is one reason why we DO NOT just hang the evaporator in our res.....
The other reason, the evaporator coils are copper, which will leach into the nutrient.....



SWEET!!!
The A/C is now a Chiller, but now we have to get it installed and tested out.....

OK, now the chiller is done, we can get it hooked up now.....



First some pics of the finished product.....
http://forum.grasscity.com/attachment.php?attachmentid=908256&stc=1&d=1340418191

http://forum.grasscity.com/attachment.php?attachmentid=908258&stc=1&d=1340418228


http://forum.grasscity.com/attachment.php?attachmentid=908259&stc=1&d=1340418263



I was going to build a box for that control, but got excited to get this done....
So maybe later when I do the exhaust I'll put that control in a sealed box....



OK cool, so now I just put in my pump, hooked it up to Wort Chiller coil, hung the coil in the res, and put the return
in the chiller's res... I also added a mixing pump inside the chiller coils, not needed, but I has a spare one... LOL
http://forum.grasscity.com/attachment.php?attachmentid=908265&stc=1&d=1340418548

http://forum.grasscity.com/attachment.php?attachmentid=908266&stc=1&d=1340418696


http://forum.grasscity.com/attachment.php?attachmentid=908267&stc=1&d=1340418806


http://forum.grasscity.com/attachment.php?attachmentid=908268&stc=1&d=1340418839





The cool part, by using the A/C's temp sensor in the chiller's res, with on the lowest setting, the chiller res stays 50°!!

I would like to see 40, but I'm good with 50, because the chiller's compressor only runs for 5 minutes to drop the chiller's res down 10°, so the chiller kicks on at 60° and shuts back off at 50°.....



Now all I have to do is control the flow through the chiller coil in the nutrient res.....
I'm going to do this with a CAP TMP-DN, it's simply going to control the on and off of the chiller water through the coils...




Tomorrow I'm going to install some ducting on the back of the chiller so I can dump the heat into the central exhaust..
Then this conversion is a done deal......

Not sure if I posted about the testing.....
But res temp was 78° and after 30 minutes it was 67°....
The chiller's compressor shuts off when the chiller's res is at 50°F....


When the pump is on chilling the nute, chiller's compressor comes on at 60°K and off at 50°F..
It takes about 15 minutes for it to come on and runs for about 3 minutes before shutting back off again....
So to drop the res temp 10°F, the chiller's compressor cycles 2 times and runs 3 minutes each time...

Edited by jakesterjammin, 23 June 2012 - 03:29 AM.

Beautiful JJ, love the chiller! Brilliant idea!

Best thing is the old lady fueled your motive! Good girl!

So without my wife fueling my desire for DIYing shit I would have spent $130 for this DIY chiller...
Again, right now I'm only looking to cool down maybe 100gal total...


But now the wife went out and spent $104.00 it jacked up my cost to 234.00..
If I would have just bought the new A/C to begin with, the total cost would have been around $215.00


And STILL a far cry from a 1/2hp @ $500 and even a 1/4hp @ $400....
So I figure it's a cheap way to cool 100-150gal...





Update pic.....

well done jj
now i need to find an ac local and get working.

thank you very much for the DIY.
a middy

Thanks you guys....

Also ML, I wish that I had a small old cooler...
That would have been perfect, but all I had handy was the old toolbox....

Right now I'm using the Styrofoam pieces that the A/C was packed in to insulate the chiller's res...
That Styrofoam and some spray foam insulation called "Stuff"...........

Another great American product...
I'll post up some pics later when I'm all done....


Also, this morning I went down, the chiller's compressor was not running, the chiller's circulation pump was running (pump that cycles the cold water through the coils in the res), and nutrient res temp was 70°... As I was working down there, the chiller's compressor cycles once for about 4 minutes, and then about 6-7 minutes later the chiller's circulation pump shut off....


I checked the nutrient res's temp and it was 65°....
So it seems I have a 5° difference from the time the chiller's circulation pump turns on to cool the res down,
to the time it shuts off at desired res temp...


I wish that was more like a 3° difference, but oh well....
Keeping the res between 65 and 70°F, I'm happy with that......

I cannot rep you any time soon but I will be. +Rep

That some serious Mad Scientist Stuff !

Good Vibes

I posted this in my grow thread but wanted to post the data here too..

After 24hrs of use, here is how this conversion is working out for me....



Right now the chiller's circulation pump comes on at 70° (21°c) and off at 65° (19°c)....

That works out perfect for me, because I get about 3° raise in temp after a flood..
So we start at 65° (19°c), after a flood the res is around 67-68° (20-21°c), then after the second flood,
it kicks on the chiller's circulation pump and chills it back to 65° (19°c)....


The chiller's compressor only cycles once in the cool down and for like maybe 2 to 3 minutes tops..
It takes about 5 maybe 8 minutes tops to drop 45gal res down 5° once the chiller's circulation pump kicks on...



Now I want to have the chiller feed a manifold, which will allow me to run lines up into the chamber for the DWC tubs..
That way I can run some accurate nutrient tests maintaining suggested nutrient temps....

Thanks you guys....

Also ML, I wish that I had a small old cooler...
That would have been perfect, but all I had handy was the old toolbox....

Right now I'm using the Styrofoam pieces that the A/C was packed in to insulate the chiller's res...
That Styrofoam and some spray foam insulation called "Stuff"...........

Another great American product...
I'll post up some pics later when I'm all done....


Also, this morning I went down, the chiller's compressor was not running, the chiller's circulation pump was running (pump that cycles the cold water through the coils in the res), and nutrient res temp was 70°... As I was working down there, the chiller's compressor cycles once for about 4 minutes, and then about 6-7 minutes later the chiller's circulation pump shut off....


I checked the nutrient res's temp and it was 65°....
So it seems I have a 5° difference from the time the chiller's circulation pump turns on to cool the res down,
to the time it shuts off at desired res temp...


I wish that was more like a 3° difference, but oh well....
Keeping the res between 65 and 70°F, I'm happy with that......

as i happens i do have an old travel powered coolbox that died .
could you not fix a bit of polystyreen to act as a float to raise the coil in the res ? would that help give you that 3* your looking for ? but what do i know i'm a sodin chippy
middy

as i happens i do have an old travel powered coolbox that died .
could you not fix a bit of polystyreen to act as a float to raise the coil in the res ? would that help give you that 3* your looking for ? but what do i know i'm a sodin chippy
middy

Ya that's what I did now....
I secured the chiller's temp sensor to the its res, and then adjusted it...



So here is an addition which I had setting in my desk collecting dust...

http://forum.grasscity.com/attachment.php?attachmentid=908784&stc=1&d=1340485426


http://forum.grasscity.com/attachment.php?attachmentid=908785&stc=1&d=1340485426



So now I can monitor both chiller res temp and nutrient res temp...
In a couple months the Trashcan nutrient res will be swapped out for a 100gal and 5 more sites added to the system..

Oh and the nutrient temp above is only because I'm refilling the res for a change to flower nutes...
It's just water in there now....

flower nutes

OK, I been watching this thing all day and I can set both chiller and nutrient res to whatever temp I want...

Chiller Res: On @ 50°F and Off @ 45°F
Nutrient Res: On @ 71°F and Off @ 68°F....


Again it takes about 5 minutes to drop the 3°...
The chiller's compressor comes on once every other "res chill down" and runs for about 3 minutes...
So with results like this, I see NO PROBLEM chilling around 150gal on the hottest of days....


http://forum.grasscity.com/attachment.php?attachmentid=908872&stc=1&d=1340491466

OK, more pics.........


Well MIDLIFE, it's not the prettiest Pig in the poke, but it dam sure gets the job done....



So here is what I did...
Again, I wish that I would have seen an old cooler in my hunt.....


I took the a can of "Great Stuff" which is just spray insulation that expands and turns into Styrofoam ($3.99 a can)..

http://forum.grasscity.com/attachment.php?attachmentid=909036&stc=1&d=1340508564




Then I took the Styrofoam the new A/C unit come packed in, cut it up, sprayed the back of it with "Great Stuff"
and then stick it to the toolbox, then taped it in place until the "Great Stuff" jelled up (15 min)......

Once I had the 3 side of Styrofoam stuck on to the toolbox, I started filling in the cracks...
Again this really is "Great Stuff", because it expands and works its way into all the cracks and crevices...
After an hour or so, it turns into Styrofoam and now you just take a sharp knife and trim it up...


Tossed some duct tape on the corners......
Because NO Hillbilly project is complete without Duct Tape!!!



Here is what I ended up with..........
http://forum.grasscity.com/attachment.php?attachmentid=909039&stc=1&d=1340509061


http://forum.grasscity.com/attachment.php?attachmentid=909040&stc=1&d=1340509099


http://forum.grasscity.com/attachment.php?attachmentid=909041&stc=1&d=1340509133




Now to show you how thick the Styrofoam is.............
http://forum.grasscity.com/attachment.php?attachmentid=909043&stc=1&d=1340509200


http://forum.grasscity.com/attachment.php?attachmentid=909044&stc=1&d=1340509229




So I decided to turn the chiller down some and open her up a little....



OMG in 12 minutes I had to take my foot off the gas or I was going to wreck into a pole or something!!!......

http://forum.grasscity.com/attachment.php?attachmentid=909050&stc=1&d=1340509414



2hrs later I come back and it's the exact same temp....




Now what this proved to me that this can also be reversed.....

Meaning, we can run sub-zero temps in this small chiller res, then run the coils through the chiller's res....
So now you would pump your nutrient through the coils which are in the sub-zero temps of the chiller's res....


The same way as a manufactured chiller would do....
All they are doing is taking a stainless steal tank, putting an evaporator in it, and getting it to sub-zero temps...
Then you pump nutrient through the chiller's coils submerged in sub-zero temps....

You would have to use Anti-Freeze good to -50, because these 5K BTU A/C units will pull a small res
down to around -35°..
Or maybe a washer fluid, which is good, but is flammable as well...


Water has the best heat transfer properties though...
And one reason I choose to go with the coils in the nutrient res, pumping chilled water through them...
Well that and I was lazy, not wanting to buy the stainless steel tubing and coil it myself....
So I bought a Wort chiller which really is made for 5gal buckets....



This conversion is finished..... and time to

Edited by jakesterjammin, 24 June 2012 - 04:30 AM.

great work as always jj,

this will help many many growers on GC and many other sites also once the word starts to get around , make yourself a ´jj chiller´ man will be the word on the web.

I vote for a sticky..
middy

I don't know shit about hydro...lol but this is cool! You want to keep the water cool I presume because warm water grows bad shit or harms the roots? Scoop me.