Glycol chiller issues?

[USMChueston0311]

im running a DIY chiller from a 5k BTU AC, in a 38 at cooler at 20 f. Fermenter is a CF15 spike, with cooling coil and package. It’s been sitting at 39.2 w a set of 38 for like 30-45 minutes and is not dropping.. is it normal for glycol chillers to have a hard time dropping temps? Or am I possibly having an equipment issue?

 

[auburntsts]

From what I've read, 20F for your glycol seems too cold. Your coils might have iced up inside the conical. Have you tried dropping the set point a deg or 2 to see if the system responds?

 

[USMChueston0311]

It’s atill flowing out of the return line. But I just increased to 25. Lets see how that acts.

 

[auburntsts]

It’s atill flowing out of the return line. But I just increased to 25. Lets see how that acts.

The ice I'm referring to is on the outside of the coils, a beercicle if you will. I'd still try to drop the set point on your conical to say 36 to see if the temp drops any from 39. What differential are you using on your temp controller?

 

[USMChueston0311]

Just set comics tom37: nnutmif it can’t pass 39-38 how will setting it lower have. Any difference?

 

[USMChueston0311]

I’m using the spike controller which isn’t programmable. It kicks on when temp goes .5 above or any below.

 

[mikehoover]

I had the same problem when testing my new set up. I have the 5000 BTU AC with a 48 quart cooler. I had 7.5 gallons of 33/67 glycol solution. When I set it at 20F to crash the test water (1 BBL volume with 50 ft 3/8" ID stainless steel coil inside), it would not go lower than 39F and the chiller evaporator coil would ice up. I now have it set at 26F, but yet to try to crash test it again as I have an ale fermenting currently. I read on another forum post that someone was having great success with a 70-quart cooler, i.e., more glycol solution, so that is something to consider. Once I have the ale in kegs I may test it again to see if I can get it lower than 39F. Also, my fermenter has two layer of Reflectix (R Value ~ 6) around the fermenter. I may add another layer.

 

[USMChueston0311]

So with keeping my glycol reservoir a little warmer, around 25, and my conical temp at 38, it seems to be handling it just fine. With the spike system, this is their recommended parameters, and it seems to be working for me. May differ from setup to setup, but I’m happy with it.

Also spikes cooling coil has an in and out, and one side is to be used when temps are above 40f and the other when below 40f, as there is a cooling inversion that happens. Something else to think about and check with your coil.