My young bloke has been making a bit of beer, and modified an old fridge so that he could have a controlled temperature fermenting environment.
When I first started doing spirits I did a couple of ferments using the Still Spirits Turbo packs. For what ever reason, the end product had a bit of an acetone type smell about it, and even after running it through a reflux still a second time it was nothing special. As it was summer when these ferments were done, we assumed the high temperature might have caused some of the poor flavour we experienced.
Since then we have done a few Tomato Paste Washes, and these have given us a very good quality neutral product. As it has cooled down with winter coming on we seem to be taking longer and longer to have fermentation complete.
Our latest hardware change is to set the old fridge up to keep the fermenting product warm to help reduce the time for fermentation to complete during winter. Previously the fridge was using an STC-1000 temp controller to switch power on and off to the fridge motor to maintain a constant cool temperature which we could accurately set. Because the weather has cooled down, we now want to use that controller to warm the fridge chamber up.
To this end we have unplugged the fridge motor from the STC-1000 and plugged in a Ryobi heat gun which is set to the lowest air flow and lowest heat setting. We sat the heat gun on the floor of the fridge facing upwards. It is possible to place your hand 1 inch in front of the heat gun nozzle and the air flow is not hot enough to burn you. The temperature controller is set to maintain a temperature of between 34 and 35 degree celsius inside the fridge. Currently I have a 5Kg sugar, 25 litre total, Tomato Paste Wash in the fridge fermenting.
A 50 litre keg will also fit inside the fridge OK.