I got the ranco digital temp control for my fridge. I set the temp at 62 with a +/- 2. The temp has been 63-64. At first the wort was spot on at 64 but as fermentation began to get active it rose to 66/67. The question is do I adjusts fridge to lower the temp or next time start at a lower temp and let it rise to like 64. I didn't want it too cold and prevent yeast activation. The bigger or overview question is let's say I want to ferment at 66. Do I start the ferment at 62 and let it rise to 66 or start it at 66 and let it rise naturally and then fall naturally keeping the ambient temp the same? Or as it rises lower the ambient temp to stay within the target temp? I am brewing a pale with dry yeast us-05.
There are many ways to skin this cat. I usually do it by setting the fridge controller so that the ambient (fridge air) temp averages about 7F below the desired fermentation temp. A second controller controls a heat wrap which is wrapped around the fermenter. That second controller is set to the desired fermentation temp, and its probe is in a thermowell in the wort. With this setup, you can lock in your wort temp pretty tightly throughout the whole fermentation. If you want to start lower and ramp up, just start the controllers lower, and increase their settings whenever you want. (And toward the end, you can reduce the 7 degree difference to a narrower difference.) ETA: This method also facilitates doing two different fermentations in the same fridge, assuming their desired fermentation temps are fairly similar, but not (necessarily) the same.
You should be trying to control the temperature of the wort, not ambient. You'll probably have a difficult, if not impossible, time trying to keep your wort where you want it, when using ambient to try and control fermentation temps.
I saw a video of inserting the probe into the wort. Currently my probe is just set up to read the ambient temp. If the probe was actually in the wort that might help control the temp more right?
Until I can afford another ranco and heat wrap if I top the one ranco I have and inserted it into the wort would that work better?
Your goal is the temp of the wort. I start my wort one or two degrees below target, then as fermentation starts allow it to creep up to desired temp. As ferm activity increases this will require you to lower ambient. Then as fermentation decreases you will raise ambient again. I find a thermowell with a probe for wort temp to be essential, this tells you what's going on in the primary. Monitoring the wort temp and adjusting the ambient can be done with as little as checking twice a day . My experience is it will not skyrocket in an hour or two, rather half-a-day or so for movement. You know what to expect so it's not too hard to stay ahead of the game. I call this: cut, peel, quarter: I would not recommend inserting your controller probe into the thermowell. As a minimum this will give you a ±1° swing. Fairly sure you can beat this with monitoring wort temp and adjusting ambient. When it's really hot outside you will want to increase your differential to prevent short cycling your compressor. I find if the fridge cycles every 60-90 minutes the wort temp doesn't even flicker. On summer days I set a differential of 8. For the most part, if there is an error I prefer to be on the low side. Also, if considering putting the probe directly in the wort, I have seen no info that the Ranco probe is waterproof (anybody know?).
Possibly. I tried it this way years ago, but (at least with my fridge), by the time the wort cooled down to the point that the fridge shut off, the fridge air temp was really cold, and the wort temp tended to over (under?) shoot the target before everything equalized. But YMMV.
I was trying not to tinker too much and not open the fridge very much but it sounds like a little management is required. I am a full 48 hours since I pitched the yeast and 24 hours since solid fermentation. Would you recommend lower the temp or just letting it ride and make changes on my next batch?
With US-05 you will probably be safe with the low 60s, so I would tend to tinker and lower the temp (especially for the next 48 hours). This is an aquarium thermo with a probe that fits neatly in a thermowell and the line snakes through the door. Place it by your Ranco and you can see both temps (ambient & wort) without peeking inside.
As has been noted, I wouldn't put the probe directly into the wort. I attach the probe to the carboy, and insulate it against ambient. FWIW, I like to bring the wort down a couple degrees below my target, before putting it in the ferm chamber.
Ranco probes are NOT submersible. There are submersible temp probes on the market either k-type thermocouples or specific to the thermometer. I recently bought one for my Thermoworks DOT that I use to set an alarm for heating strike/mashout water and monitoring mash temps. I would let your current fermentation "ride" as is and take good notes on your differential. Your differential will change from batch to batch depending on the OG. That is....... if you don't get a thermowell and directly control the temperature of the active fermentation itself. Which I highly recommend because (at least to me) a 1 degree or less swing is much more finite than chasing a delta between ambient air and actively fermenting wort.
