Second hand fridge with an inkbird thermostat.
I don’t have a heater in there, but from my brews before the fridge the problem was keeping it cool, not warm. Does anybody with more experience than me have thoughts on why I might need a heater?
Looking forward to trying this out in a few weeks.
Certainly don’t load 25 kilos of brew on the glass counter :D
Heating may come useful if you need to kick a slow ferment into action. I have borrowed a hair dryer if I needed this, just plug in to the Inkbird :)
I use a similar setup for settling after fermentation. I’ve propped up the shelf with a vertical board cut to length. No troubles so far.
I use a seedling starter mat. I tend to brew when it’s cold enough that I sort of don’t need the fridge (but it would help) and it keeps it about 3-4°C above ambient no problem, even after fermentation.
Generally, when you want to heat the beer is after fermentation has peaked. Higher temps means faster fermentation (obviously to a point), and fermentation generates heat (positive feedback loop), which is why you need to cool beer through the initial stages of fermentation). After peak though, the temperature drops and causes a positive feedback loop downwards. This means that your beer really crawls to the finish line. Your beer might be 90% done after 3 days, but then take a couple weeks for that last 10%.
Another benefit is if you are bottling the beer, you need to know how much sugar to add. Calculators ask for the beer temperature post fermentation to determine residual CO2. With a dropping temperature, it’s hard to say what that point is, and if fermentation is just stalled, not complete, you could have residual fermentation sugar. Bumping the temperature up at the end solves both problems.
I also second adding a fan. No need for anything crazy, just something little to move the air. I used a old computer case fan wired to a random DC charger from the “miscellaneous chargers” bin at the thrift store: just make sure the voltage works with the fan.
Moisture can be an issue when you are keeping a fridge above the designed set temperature, but below ambient. I just keep a long sock filled with silica beads in mine. To recharge, I can just pop it in a low oven. They sell devices to do this (evadry is the brand name), but you might get literally 20x less silica for the convenience of a case and built in heating element.
Diacetyl rest benefits from increased temps, also kveik can be fun to use at high temps.
I would also install a small fan in there, it seems to significantly help with more stabile temps, and an insulating layer on top of the probe otherwise it’s just reading air-temp and not wort temp.
For he insulation layer, I’ve seen people use sponges. Do you recommend anything else?
No i use that too, works well and it’s cheap.
You’ll notice a difference, I built a fermentation fridge like a decade ago, brewpiless controller and added a greenhouse heater. Absolutely notice the difference.
The main use of heaters in this setup is to make the “spring” of oscillatory heat system “stiffer”. This should make temperature oscillations faster and smaller in amplitude thus bringing process to more stable state. This is mostly important when you have set temperature close to ambient outside, otherwise you’ll inevitably leak a few watt through fridge insulation anyway, and if it’s not enough you can always prop the door open. Latter would lead to humidity buildup though. If you set process to 20C, obviously, no leak, huge slow oscillations on heating phase.
Then there is diacetyl rest, I’d just recommend taking that thing out for that.
