I just hooked up my Johnson A419 to my chest freezer yesterday for a Scottish Ale I'm brewing. Seems to be working well taped to the side of the carboy with a gel pack and bubble wrap on top of that but I was wondering if it matters to have the freezer set to the maximum cold setting, minimum, or in between?
My target fermentation temperature is 64, I have my freezer turned to 6 (the maximum setting) and my A419 settings are as follows:
SP = 65
Diff = 1
ASP = 12
Even though the differential is set to 1 it doesn't actually cut out until the temperature difference is greater than 1 degree so it cuts out at 63.99 (I guess?) but at that point my probe temp will continue to drop until it eventually reads 62 where it sits for an hour or so before climbing back up to 63. It stays at 63 for another hour or so and slowly climbs up to 64 where it sits for another hour or so, etc.
64 is the minimum recommended temperature for my Wyeast 1098 so I'm a bit worried about it dropping down to 62 although I really don't think 1 or 2 degrees will have any significant difference other than fermentation might take a bit longer to complete but I'm not worried about that.
Do you guys who have used temp. control units set your freezer to the maximum setting? I'm thinking if I turn it down maybe the temp. won't drop down to 62 after the cut out point. Or will it matter?