Temperature Controller for Fermentation

Today, I will be detailing the temperature controller for the planned fermentation chamber.  I had read a lot about the STC-1000 controller and see it on eBay for around $20.  I started to research the module and found that is came from China and reported the temperature in Celsius.  Living in America, this was an inconvenience, but not insurmountable.  Then I happened across this thread on HomeBrew Talk:


User alphaomega had written new firmware for the STC-1000 to display in Fahrenheit and to have different fermentation profiles.  A couple people decided to flash them and make them available for the public without the need for an arduino to upgrade the firmware.  One such person was found at Brews By Smith.  I opted for the DIY kit with the tri-color LED.

DIY full kit with STC-1000+ and tricolor LED – including shipping – $80.00

It shipped quick and I got it quickly.  This is what was in the package : project box, controller and power cable:

Upon opening the project box and the controller box, we see the goodies for our DIY enjoyment

The first thing I noticed was how SMALL this controller is.  Here is a picture of me holding it:

A picture of all the items inside the project box:

The tools needed for this project are: a soldering iron, wire cutters and a a screwdriver with both phillips and flat tip bits.

The instructions are found here:

DIY Instructions

There were only a couple inconsistencies between the instructions and the actual installation.  It was a pretty simple build, though.  First, I placed the input and output power receptacles into the box and snapped the wings into place.  Notice that the heat and cool receptacles are marked.

Then I soldered the ground wire on (green) followed by the neutral (white)

Before the wiring got too busy, I soldered the leads on to the temperature probe receptacle

And then I installed the receptacle into the box.  This is one of the inconsistencies.  There was no mil-spec grommet to install into the box.  That must have been the old way to install the probe.  With this new way, you push the receptacle through to the back of the box, put on a washer and secure it with a nut.

[**UPDATE**]  Just prior to publishing this write-up, I contacted the seller about the inconsistency noted above.  He had just started shipping out the new connector and did not have time to update the instructions.  I must say, the new connector is a far superior method and I am SUPER pleased with the service given.  He has always responded promptly to any inquiries.  Please, do note that this is not his day job, but a hobby to help out the rest of us.

I then soldered the hot leads onto the receptacles and created the pigtail with which to connect the power to the terminal blocks.  This was the other thing I changer.  Instead of using the crimp connector that was supplied, I used a wire nut and then wrapped it with electrical tape.

This picture shows all the leads connected to the terminal blocks.

I then pushed the controller into the box and slid the side retaining clips onto the controller.  The LED is a push fit into the LED holder to the left of the controller in this picture.

Then I soldered the male connector to the end of the temperature probe.  Remember to slide the connector cover onto the wire before soldering here, or you will end up taking it apart.

Here’s a picture of the probe plugged in to the controller


All in all, like I said, this was a pretty simple build.  Having the machined project box and all the smaller parts already provided greatly added to the ease of this project.  I am certain that to build this with the quality shown here, it would have easily cost more than the kit that was ordered.

Now, I can’t wait to build the fermentation chamber!

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