Replacing the Temperature Controller on my Freezer - Home Brew Forums
Home Brew Forums > Home Brewing Beer > DIY Projects > Kegerators & Keezers > Replacing the Temperature Controller on my Freezer

Reply
 
Thread Tools
Old 10-26-2013, 03:22 AM   #1
_TheTrevster_
Recipes 
 
Aug 2013
Kalamazoo, Michigan
Posts: 21
Liked 9 Times on 5 Posts



In this thread I will describe the steps I took to replace the stock temperature controller that came with my Chest Freezer with an aftermarket controller. Most of the temperature controller threads I have seen involve creating an outlet that the controller turns on and off, plugging the freezer into that outlet, and then hanging the probe inside the freezer. My preference was to utilize the existing space to create a cleaner and simpler design. I initially intend to use the freezer as a fermentation chamber, and have future plans to modify it further into a Keezer. The steps I took for this project were gathering supplies, removing the old controller, and installing the new controller in its place.


Step 1:Supplies
  • Chest Freezer (Mine is a 7.0 cubic foot GE Chest Freezer (model FCM7SUBWW).




  • 12 gauge stranded copper wire
  • Twist-on Wire Connectors


Step 2: Removing Old Temperature Control
First I removed side vent, which let me access the clips on the back of the front face plate. I removed the clips, and was able to detach the face plate from the freezer. The connection I had to unplug were the positive/negative for the ‘Power On’ light (Red/Black & White/White), the positive/negative for the temperature control unit (Red & Black), and the natural ground (green).

The only connection left was the temperature probe, which came inserted into a plastic tube into the bowels of the freezer. I pulled this out and removed the entire controller. This left a hole in the front of the freezer where the previous controller and faceplate were.



Step 3: Installing the New Temperature Controller
The first task was to remove the connectors from the ends of the wires for the old controller, which looked like this:

I cut them off and stripped them. Next I cut four 6” lengths of wire, stripped them, and inserted them into the new controller. I now had bare wires coming out of the freezer, and bare wires coming out of my new temperature controller. All that was left was to connect them. This diagram outlines the connections I made.

Using the stencil that was included in the instructions, I measured a spot for the controller on the lid of the junction box. I cut out the stenciled shape with a coping saw, though a Dremel or other power tool would have been much easier. I set the junction box lid, now my new faceplate, into place and primed the screw holes with a drill. I inserted the new controller into the freshly cut lid, and connected the loose wires to the freezer’s wires using the twist-on wire connectors. I inserted the new temperature probe into the plastic tube that housed the old probe. Before I screwed the new face plate onto the freezer, I tested to make sure everything was working properly.
Success!



3
People Like This 
Reply With Quote
Old 10-26-2013, 03:28 AM   #2
NTXBrauer
Recipes 
 
Sep 2013
Dallas, Texas
Posts: 1,142
Liked 152 Times on 117 Posts


Nice job. I built a temp controller, with an external utility box, using the same digital controller you have. I like how you were able to integrate it into the front of the freezer where the original control panel was.


__________________
"A fine beer may be judged with only one sip, but it's better to be thoroughly sure." -Czech Proverb

 
Reply With Quote
Old 10-26-2013, 02:23 PM   #3
Seven
Recipes 
 
Jan 2011
Pittsburgh, PA
Posts: 1,539
Liked 166 Times on 79 Posts


Nice job. Does that controller allow you to set a temperature range to prevent short cycling the cooling unit?

 
Reply With Quote
Old 10-26-2013, 08:16 PM   #4
_TheTrevster_
Recipes 
 
Aug 2013
Kalamazoo, Michigan
Posts: 21
Liked 9 Times on 5 Posts


Thanks for the feedback!

@Seven: Yes the controller does allow you to adjust the temperature range. The default is 2 degrees, but I upped mine to 3 degrees to reduce the number of cycles. It also lets you specify whether its heating or cooling, delay the start, and offset the temperature for any corrections that may be needed. Here is the Diagram that comes with the unit.

CP is the temperature range, i've heard this referred to as the hysteresis cycles, but the manufacturer classifies it as "Slewing Range".
CA is the temperature correction, I have mine set 3 degrees, because my probe is built into the wall of the unit, not hanging free in the freezer.

Hope that helps, it's an amazing unit for the price. You could defiantly get a higher quality one with more features, but at $14.66 you can't lose.

 
Reply With Quote
Old 10-26-2013, 08:28 PM   #5
dbrewski
Recipes 
 
Oct 2011
Indeterminate
Posts: 1,014
Liked 52 Times on 46 Posts


Well done. I have a Frigidaire I want to use as a fermenation chamber and a very similar controller. This is a very clean way to do it, hope I have the same panel.

 
Reply With Quote
Old 10-26-2013, 08:59 PM   #6
TNugent
Recipes 
 
Oct 2013
Twin Cities, MN
Posts: 177
Liked 22 Times on 19 Posts


Nice work, thanks for the write-up!

 
Reply With Quote
Old 10-26-2013, 09:08 PM   #7
Oddball
Recipes 
 
Aug 2011
Montreal, Quebec
Posts: 209
Liked 13 Times on 11 Posts


I did the same thing with mine, but I haven't added a nice plate like yours (haven't got to it yet). The temp controller is just hanging out in the opening for now. The only problem that I have without the added heat source is that sometimes it gets too cold when I am lagering. If the temp is set very low the compressor will come on and end up dropping about two degrees lower than what I set it. I think maybe the censor recognizes that the temp has reached the target but because it is a new unit the combination of the compressor working very hard and the insulation ends up dropping it a bit lower.

 
Reply With Quote
Old 10-30-2013, 03:34 AM   #8
_TheTrevster_
Recipes 
 
Aug 2013
Kalamazoo, Michigan
Posts: 21
Liked 9 Times on 5 Posts


@Oddball: I believe the way this unit (and the STC-1000) works is that it cools/heats until the probe reaches the set temperature. I know this sounds obvious, but if you have your controller set to 34 degrees to lager, the compressor will be on full blast until 34 degrees. This may account for the temperature dropping below freezing. I suggest initially setting your controller to a higher setting (40 degrees?) and then dropping it down in the increment that your "slewing range" is set to.

 
Reply With Quote
Old 12-02-2013, 09:09 PM   #9
fleetmack
Recipes 
 
Nov 2013
Posts: 22
Liked 2 Times on 2 Posts


new poster to homebrewtalk here. I've read many posts on how to install one of these STC-1000 and, until this thread, it has appeared that people have been adding an STC-1000 to work in tandem with the existing temp. controller. So the STC-1000 will tell the existing controller when to turn on the compressor.

It appears your method is to remove the OEM temp. controller altogether, and simply install the STC-1000 as your sole temp. controller. So my questions:

1) Am I correct in what I am seeing here?
2) Am I over-thinking this? This method seems way more simplistic than using the STC-1000 in tandem with the OEM temp. controller. Why don't more people do this?
3) What are the pros/cons of this method vs. using the OEM temp controller + the STC-1000?

I should note that I'm only interested in cool temps to chill my beer, not heating the unit.

Thank you!

 
Reply With Quote
Old 12-03-2013, 02:14 AM   #10
day_trippr
Recipes 
 
May 2011
Stow, MA
Posts: 16,886
Liked 2837 Times on 2125 Posts


fwiw, I'm pretty sure a wire is transposed in the "after" diagram.

The black wire from the plug should be going to the controller pins 3 (power) and 1 (or 2) for the relay to the compressor. The other black wire should go from the relay pin 2 (or 1) to the compressor.

As drawn the controller would never power up...

Cheers!



 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Best way to keep fermentation temperature with new freezer and Johnson controller? micfiygd Equipment/Sanitation 5 05-06-2013 05:33 PM
Keezer Temperature Controller Without Changing Freezer? Jif Bottling/Kegging 9 03-29-2012 03:34 PM
Need advice regarding running temperature controller into freezer walrusbt Beginners Beer Brewing Forum 23 07-27-2011 03:58 AM
Cheap Temperature controller for freezer. Mayotruck Fermentation & Yeast 12 03-25-2011 12:08 AM
Fermenting in a freezer (with a temperature controller) thrstyunderwater Beginners Beer Brewing Forum 2 11-04-2009 07:03 PM


Forum Jump