Well I got busy and put the fermentation temperature controller together. My house is a rental with baseboard heat and with the outside temps dropping the inside temps aren’t very stable and with the cost of electricity I don’t really feel like maintaining the house temp at optimal ale fermentation temps 24/7. Temperature control during fermentation is very important so heating or cooling the fermenting beer is more economical than heating or cooling the whole house so the project was born.
I’ve slowly gather the bits and pieces but been putting it off for a while because I chose a small enclosure and getting all the wiring together correctly in the small space didn’t excite me. It is based on the commonly used STC-1000 controller that is easily found on eBay for $20-$30 with temp sensor. I used a 4″X4″X4″ water-tight electrical enclosure from Home Depot and pieces of 16GA electrical cord laying around. Wiring is straight forward with included diagram or the numerous diagrams online. Everything went together quite easily and by mounting the STC-1000 in the upper half of the enclosure there was ample room for wiring.
Setup is just as easy with the included instructions and allows control of temperature set point, differential and compressor delay when connecting to a refrigerator or freezer to lengthen the life of that appliance. I chose a rather tight temperature differential of 1 degree celsius to avoid big swings in fermentation temps. The temp sensor is either attached directly to the side of the fermentor or inserted into a thermowell that is placed through the same stopper as the airlock. Thermowell stoppers are $25-$35 online through many of the larger home brewing suppliers but attaching the sensor to the side of the fermentor is free and works just as well. A tip I have come across regarding the sensor is when attaching it to the side of the fermentor one should cover it with foam or a small piece of bubble wrap so that it is sensing the fermenter temperature and not the ambient air temperature.
Next step is acquiring a small refrigerator to use as a fermentation chamber that will allow me to heat or cool the fermenting beer to the required temp according to the type and style of yeast used. Until I find a deal on a refrigerator I’ll at least be able to use a heating pad for my next batch I brew.