Where is YOUR ferm chamber probe?

[Zepth]

I've searched a few times and a variety of answers appear, usually with thermowell and insulated against the fermenter side being the top 2. I wanted to get a actual numerical value with how many people use what method. Preferably with a why post.

As I see it:
Thermowell
PRO-Most accurate wort readings
CON-Requires dedicated piece
PRO-Least responsive to ambient air
CON-Adjusts chamber based on one fermenter

On the side, insulated from ambient
PRO-Slightly less accurate than thermowell
PRO-Inexpensive
CON-Must be detached and re-attached as new batches come and go
PRO-Measures fermenter fairly accurately

Probe jar
PRO-Inexpensive
PRO-Set and forget (no moving from batch to batch)
CON-Requires a "delta correction" for controller setting vs fermenter (con)
PRO-Allows multiple fermenters with a controlled ambient
CON-Not the most accurate reading of fermenters

Just hanging in the air
PRO-No setup
CON-May lead to wild temp swings

Other
-There has to be a method I couldn't think of at this time

With 3 batches in the chamber at this particular point in time, I am using the probe jar. I don't foresee any huge reason to switch it up at the moment. Having a chamber where I can set the ambient is a huge improvement over looking at the 2 week weather forecast and hoping for the best method which I've been using just over a year now. Where do you weigh in on the issue and why?

 

[ol-hazza]

On the side, insulated! (mines under 2" of polystyrene and held in place with a bungy cord)

Thermowell would be great but also unnecessary expenditure IMO.

The reason I choose this method over a probe jar is that fermenting beer is at quite a different temperature to the water in the jar, especially if they are on different levels in the chamber (mines an upright fridge) and this gave me issues initially

 

[CGish]

I use a chest freezer controlled by a BrewPi, so I have thermowells and an open air chamber probe. I use the thermowell for active fermentation and the ambient probe for cold crashing. I added an arduino with several additional probes so I can track the additional fermenters the BrewPi does not monitor.

Here is the freezer with 14.5 gallons of Hefeweizen fermenting:



The ambient probe is attached to the lid, putting it in the top center of the chamber with the lid closed:

 

[LandoLincoln]

Duck taped to the side of my carboy. I guarantee you the temperature of the center of my carboys and the probe are reading within a degree or two of each other. Thermowells are useful for paranoid brewers and maybe pro brewers that have gigantic conicals, but that's about it.

 

[hunter_le five]

Thermowell. Probably overkill, but it was only $12.

 

[BrotherGrim]

Considering I used to ferment in the coolest part of the house, getting a chest freezer with temperature control was a massive step forward.

I keep my temperature probe in a growler full of sanitizer. I recognize there is a temp difference between the fermenter and the probe temp due to the heat given off by fermentation, but with 5 gal batches, I don't think it is too drastic, and I am sure my temps are well within the acceptable range for my brews. My beers are good to me, and apparently others like them as well as I have won awards with the results.

Boils down to doing what you think will work for you. Good luck!

 

[Browningbuck]

i had an issue with long cycling inside the thermowell. ambient air was -5*F and the unit was still running. i found that resting it just on the ledge at the rim of the well allowed for the fridge to be happy and temps to hit where i need them.

 

[JayDubWill]

I use better bottles for primary fermentation and set it directly on top of the Johnson (A419) probe in my chest freezer. My temp swings are generally about 2 degrees +/- from what I have it set to. A friend of mine uses a brew pi setup and can maintain temps within .5 degrees. That being said i'll probably switch to something like this if I can find one.

 

[Gavin C]

Mine is taped to the side of the carboy with a 1/2 " layer of insulation over it. Bungee cords hold it in place.

I really don't see the rationale behind investing in a fermenation temperature controled environment and monitoring the ambient air temps or temperature of a container of water within during active fermenation. Seems like a pointless excercise, one which negates any benefits of a controller.

I must be missing something.

Monitoring the ambient with multiple FV's not undergoing active (heat producing) fermentation is a different story as everything will equilabrate to ambient.

With the STC hysteresis set to 0.3C the control is very precise.

 

[zach976]

Temperature probe taped under some bubble wrap to the side of my carboy has worked best for me. I have a thermowell that I use with a separate probe to monitor wort temp. I tried using my temp controller probe in my thermowell and my temperatures were all over the place. Not sure why.

 

[ZebulonBrewer]

I just got mine up and running recently, and haven't nailed down any SOP for my probe yet, but right now, I have the RTD wrapped in a small hand towel sitting well away from the fan and heat source (ceramic reptile bulb). So far it all seems to be doing well, but I need to do watch what I'm set to and what the bucket temps are.

That said, I like the one with the probe hanging through the roof. Has to be the warmest part of the fermentation chamber. Good idea

 

[Soyben]

Temperature probe duck taped to the side of with a gel cold pack over the top of it. Super easy and very stable temps.

 

[ram5ey]

I use a thermowell on the conical and tape/insulate to the speidel. I find they work they same.

 

[kombat]

I just recently started using a thermowell, and wish I'd started sooner. Knowing that fermentation temperature is such a critical aspect of making great beer, I wish I'd spent the $15 the same day I bought my fermentation chamber/freezer. It's comforting looking over at my STC-1000's display and knowing that the temperature it's showing is exactly the temperature in the heart of my beer.

 

[kpr121]

Chest freezer. STC 1000 probe, rolled up paper towel, and duct/aluminum tape holding it to the side of fermenter, at height about 2/3 of liquid level. If I am trying to make a wild swing (say from above 120 down to pitching temp, or when cold crashing), I’ll sometimes negate the paper towel, or give a little more insulation between bucket and probe, just so the freezer doesn’t run constantly for hours.

I do wish I had some more precise control. Sometimes I get that over and undershooting volley going on. Part of that has to do with my current heat source, a space heater. Its just too much power and by the time the probe senses set point there’s a bunch of ambient/latent? heat in the chamber that keeps the temperature rising. Probably going to make the cheapo paint can light bulb heater and see if that fixing things. Otherwise I might delve into some sort of PID control, Brewpi or something. Really trying to control myself from over-geeking this though, don’t want to spend too much time or money on things that don’t have massive effects on the quality of beer.

 

[thekraken]

Duck taped to the side of my carboy. I guarantee you the temperature of the center of my carboys and the probe are reading within a degree or two of each other. Thermowells are useful for paranoid brewers and maybe pro brewers that have gigantic conicals, but that's about it.

Hmmm. Do you use any other insulation besides duct tape?... I'll report back in a week or two with an experiment.

I'm using brewpi, I have a probe dangling in the open and another in the fermenter. Brewpi uses both to control the temps.

 

[mkyl428]

I just let it hang free....

Seriously though I ferment more than one batch at a time in my freezer so I try to use yeast that like similar temps at the same time and just keep it within that range using cool ambient temps... I keep my freezer at 62° ambient and my beer always comes out great

 

[Zepth]

I really don't see the rationale behind investing in a fermenation temperature controled environment and monitoring the ambient air temps or temperature of a container of water within during active fermenation. Seems like a pointless excercise, one which negates any benefits of a controller.

I must be missing something.

I have a small condo. Air conditioners are not allowed unless they are installed over a balcony, rules aside I work with what I've got. My fermentation room (and computer room) in the summer is more at the will of the weather gods.

Unfortunately this would on occasion lead to 27 C (80F) room temperature. Few things are going to ferment well in those conditions. Having a chamber that I can set to 14C (57F) and knowing that "this batch will be X over ambient" allows my brewing to continue. Agreed that it isn't the most accurate method, but significantly improved over nothing at all.

Monitoring the ambient with multiple FV's not undergoing active (heat producing) fermentation is a different story as everything will equilabrate to ambient.

With the STC hysteresis set to 0.3C the control is very precise.

This is part 2 of why I personally went with the probe jar. I rarely have one vessel on the go.

I have heard of others who attach the probe to the most active fermenter, as it is the one most in danger of off flavours. Could this cause the problem that you end up stalling out a 70% terminal gravity brew by chilling prematurely trying to keep the active ferment in range? Other option is to keep the probe on the 1st batch in, but then the second is a slave to the ambient - which will be tailor suited to keep the non active batch in the ideal range. Possibly throwing the new batch way out of whack.

Using the jar I can hopefully at least create an environment which I can repeat the conditions that a batch was subjected to and with it bring repeatability from one batch to the next. Maybe making a "yeast strain + OG = temperature over ambient" chart is in the future.

 

[LandoLincoln]

Hmmm. Do you use any other insulation besides duct tape?... I'll report back in a week or two with an experiment.

I'm using brewpi, I have a probe dangling in the open and another in the fermenter. Brewpi uses both to control the temps.

Nope.

 

[Gavin C]

Unfortunately this would on occasion lead to 27 C (80F) room temperature. Few things are going to ferment well in those conditions. Having a chamber that I can set to 14C (57F) and knowing that "this batch will be X over ambient" allows my brewing to continue. Agreed that it isn't the most accurate method, but significantly improved over nothing at all.

This is what I'm not understanding. You have a chamber (presumably a fridge/freezer of some sort), a sensor and a controller yet you are electively choosing not to control the temperature of the actively fermenting wort. I agree with you in that an ambient of 57F is in all likelihood more than adequate for an actively, fermenting ale and will keep other conditioning batches at a reasonable cellaring temperature.

Is keeping the multiple batches at a good temperature outweighing precise control of your most recent batch the key to the approach in your case? That would make sense I suppose.

How is your air-con or lack thereof impacting the chamber's temperature? I'm not following you there I'm afraid. Mine stays at what I set it to regardless of the temperature in the house. North Texas temperature swings can be wild.

Having said all that, if the beer is good and you are winning accolades, who am I to argue with that. I certainly cannot claim to be on a par with that. More power to you. If my system was working as demonstrably well as yours is I certainly would be reluctant to make any potentially deleterious changes.

 

[Zepth]

Is keeping the multiple batches at a good temperature outweighing precise control of your most recent batch the key to the approach in your case? That would make sense I suppose.

How is your air-con or lack thereof impacting the chamber's temperature? I'm not following you there I'm afraid. Mine stays at what I set it to regardless of the temperature in the house. North Texas temperature swings can be wild.

Having said all that, if the beer is good and you are winning accolades, who am I to argue with that. I certainly cannot claim to be on a par with that. More power to you. If my system was working as demonstrably well as yours is I certainly would be reluctant to make any potentially deleterious changes.

Keeping multiple batches in "about the right zone" is admittedly a one size fits all approach. It's easy, it's lazy, no contest. My concern with focusing the entire chamber to the most recent / most active batch is that it could (would it?) lead to the other batches being jeopardized from going outside their comfort zone. Maybe I'm worried for nothing.

The chamber is a new addition to the brew setup. I'm a little sad to say that I went over a year without any real form of temperature control, and finally pulled the trigger. It's only been in functioning form for 2 days at this point. Now the room temperature won't be affecting my brewing. My mistake I should have said something about this part earlier.

My beer isn't winning anything, nor am I trying to. I cannot currently vouch for how well this system works, except for soon being able to compare it to "hoping for the best" temp control method. Part of why I'm asking this question is to gather information that may warrant changing things around. The probe jar has served me well in my keezer and seems like a good starting point. Then again this may be a moot data point since the keezer doesn't have an exothermic activity taking place within.

 

[Gavin C]

My mistake. Reading the thread again I was another poster mentioning awards. I did not intend to make a useless statement in that regard.

The probe in a water/air container works well in a keezer/kegerator as you rightly state wher no exothermic process is ocurring. Not so in controlling a FV IMHO.

Best of luck getting your setup the way you want it. Congrats on the new chamber.

 

[hifidelity]

I tape three neoprene beer koozies to the side of my fermentation vessel, and then slide the probe between the vessel and the koozies. It seems to work very well.

 

[thekraken]

Nope.

Attached is a plot of both the internal temperature and the temperature of the outside of the carboy, the carboy probe is duct taped to the side of the fermenter as you suggested with no further insulation. Internal is green line, external is the grey line.

It's pretty obvious that during peak fermentation there is a pretty big difference between the two temps.

Temp was controlled by the internal probe, next time maybe I'll control by an external probe to compare.

 

[doug293cz]

Attached is a plot of both the internal temperature and the temperature of the outside of the carboy, the carboy probe is duct taped to the side of the fermenter as you suggested with no further insulation. Internal is green line, external is the grey line.

It's pretty obvious that during peak fermentation there is a pretty big difference between the two temps.

Temp was controlled by the internal probe, next time maybe I'll control by an external probe to compare.

This chart shows why you need at least a little insulation between the probe and ambient if you tape the probe to the side of the fermenter. If you don't insulate the probe, it will not reflect the temp of the beer very accurately. You also don't want to over insulate the probe, as this will cause the chamber temp to over/under shoot the set point, as there would be a long lag time between the beer temp and the chamber temp. Since the chamber is over/under shooting temp, the beer will as well to some extent. This can be mitigated by having less insulation over the probe. The beer temp will not be quite as close to set point, but oscillations will be less. The best control appears to be achieved with a BrewPi type controller which measures beer temp (in thermowell) and ambient temp, and then uses predictive control algorithms to almost eliminate any over/under shoot of beer temp.

Brew on

 

[jahdub]

The grey and green line are close enough to each other that I feel fine about the fact that I just tape my probe to the side of whatever is fermenting and set the controller to a couple degrees cooler than my intended fermentation temp.

 

[thekraken]

It could only help to put some bubble wrap or some kind of insulation over it.

 

[azazel1024]

This chart shows why you need at least a little insulation between the probe and ambient if you tape the probe to the side of the fermenter. If you don't insulate the probe, it will not reflect the temp of the beer very accurately. You also don't want to over insulate the probe, as this will cause the chamber temp to over/under shoot the set point, as there would be a long lag time between the beer temp and the chamber temp. Since the chamber is over/under shooting temp, the beer will as well to some extent. This can be mitigated by having less insulation over the probe. The beer temp will not be quite as close to set point, but oscillations will be less. The best control appears to be achieved with a BrewPi type controller which measures beer temp (in thermowell) and ambient temp, and then uses predictive control algorithms to almost eliminate any over/under shoot of beer temp.

Brew on

Excellent post. This is why I attach mine to the side of the carboy with a bit of insulation, but not much. Also why I tend to adjust temperatures in 2-3F steps and let it equilize for at least an hour or two before dialing in more change. Sadly, all manual (ITC1000/STC1000 controllers), but it isn't that much of a hassle.

I use Ace bandages, as it is easy to attach to the side and since I can get 2-3 good full wraps around the carboy, it is providing modest insulation without going overboard.

I've done some quick checking with my ITC1000 and STC1000 both hooked up. They read within .2c of each other with the same setup. I haven't taken the internal temp of the beer as it is fermenting, but just checking with my ace bandage setup (how I started setting it up) with the one thermoprobe just hanging loss in the minifridge and then attached to the side covered with a couple of old socks that were worn out and taped over (socks folded over, so 8 layers of sock material total, about 3/4"). Just hanging lose the thermoprobe seemed to tend to read about 3-5F too low during active fermentation, It probably also would have taken a lot longer to hit the proper temperatures in the carboy as every time I dropped the temp 2F after pitching and putting the carboy in the chamber, the thermoprobe in the minifridge would also consistently read 3-4F too low for a lot of that hour or so before the carboy reached equillibrium. So if it was just hanging there, it would likely be stopping the minifridge from running too often.

With it insulated like heck to the side of the carboy, it tended to read "too high" by 1-2F, so I'd likely have more overshoots, especially as I was trying to get it to the proper temperature it would consistently read "too high" by 1-2F.