Hi everyone, Newbie here . Finally built my keezer using a 5.1 cu. ft freezer. This is made for cooling and dispensing beer only. I am using the Inkbird ITC-308 temp controller. Have it set to 40 ° with a 2° +/- differential. The unit also has an alarm high - low of +/- 8 ° set. The problem I am having is while trying to dial in my temperature, The freezer will kick on at 42° and turn off at 40° but sometimes continue to cool all the down to < 32° and trip the alarm low. The temp will then slowly rise back up to 42° over time, never really stabilizing at 40°. I can adjust the alarm low setting but I am more worried about what the low temp swings will do to my beer. A few questions... 1) Are the low temperature swings normal? I don't have my kegs in place yet so I am hoping the extra mass will help stabilize the temperature swings. 2) If adding the mass into the freezer does not stabilize the low temp swings, what recommendations do you have? 3) The freezer has a temperature dial of low to high, currently set at low. Where should the proper setting be on the freezer dial? Is it correct to assume that low setting on the freezer will cool it slower longer avoiding cooling faster at the high setting and thus avoiding quick cycling which I read is bad for the freezer? 4) Ideally, how often should your freezer cycle on ? Sorry for all the questions. Just want to do this right. Cheers!
I don't use the Ink Bird myself, others may have a specific fix for that particular digital T-Stat. In general... Try moving the probe away from the side of the cooler and place it a bit towards the top as well. Once you get it to place that works, leave it there. 2 degrees differential might be too tight and is not needed anyway. 3 or 5 will probably hold liquid temps just as steady and will also decrease cycles which is what wears out the compressor anyway. The freezer has way more cooling capacity that you need. It is likely that even after the compressor has shut down the air is still being chilled by the cold coils. The outboard T-stat works as an on/off for the compressor, but that does not mean it stops physics. If the coils are -25 degrees they are going to continue to suck heat from the box. Air temps vary a lot more than liquid. If you can place the ink bird probe in a glass of water, do that. Just be sure you can. I sometimes use bubble wrap around the probe. It helps to protect the probe and keeps it from resting directly on the cold walls of the freezer. Once temps stabilize the freezer will cycle maybe once an hour. Of course it depends on a dozen factors though. Chest freezers are very efficient, even with the top open they do not really "lose cold" when the door is open, unlike an upright which "spills" all the cold air into the room. Set the freezer T-Stat wherever. Does not make much difference. Even the lowest setting is much colder than the Ink Bird setting. The freezers dial does not change anything other than the target temperature. It doesn't get colder faster, it doesn't change the HP of the compressor. It will only set the target temp. The cut in/cut out variable is quite large, probably 8 degrees or more and it is not adjustable like the Ink Bird. And at 1, 5 or 10 it will be well below 32 anyway. So set it at 1 or 2. If the Ink Bird takes a shit you'll have 10 degree kegs which is only slightly better than -20 degree kegs. Cheers.
This is good information. Thank you! I am going to play with the probe location and consider placing it in water. I have read many articles online about whether to do this or not and figure it is worth a try. The information on the freezer T-Stat makes sense. I thought it adjusted how much cold air it kicked out. Can't thank you enough.
What @billandsuz said. The thermal mass of the beer should allow you to set a much wider differential than 2°. I would set it to 5 and pay attention for a month or so. If you can 'taste' the temp variations, then narrow it down a bit. Intuition says that the freezer's T-stat should be set to maximum cold, effectively giving the Inkbird 100% control. However, setting it higher could be useful should the Inkbird fail in the 'On' position, potentially protecting your beer from freezing (and the kegs from splitting). Very unlikely, but since it'll otherwise be doing nothing, it might be something to consider, if only for peace of mind.
Thank you. Set the +/- to 4 which has limited cycling even though it still cycles every half hour or so. Going to move to 5 and see how it responds.
I use the Inkbird (and Ranco) and rarely have my keezer drop more than one degree below minimum setting. You will most likely eliminate your problem when you add your kegs and place the probe in some central location. A word about differentials: First, there is no ± settings. It's either all plus or all minus. Say you want to cool to 38 degrees with a 6 differential . . . you set the programmed temp to 35. There are tons of youtube videos on this subject. I would not recommend placing your probe in water. Your minimum differential is 1, which guarantees you'll have a one degree temp swing. That's not horrible, but ideally you want to cycle just like your kitchen fridge (45 - 60 minutes). Have you ever gotten a drink of milk or coke or beer and thought it was too cold because it had just cycled . . . or too hot because the cycle was just about due? Nope, a full fridge (or keezer) should not have a noticeable temp change, that's your target. I'm guessing your keezer is in the home, that's ideal to get it dialed in. Start out with a couple of five gallon buckets of water and let everything stabilize . . . then measure a few liquid temps, while paying attention to cycle rate. My normal room temp is upper 70s and I use a differential of 8 (probe in air). Beer never changes temp and I haven't touched the controls in years. Just remember all controllers and thermos can have a slight error, your vote of what tastes best trumps all. Oh yeah, kudos for tackling this task before any precious beer is at risk . . .
