Placement Of Temp Probe For Tempmate

[symphony1975]

i have a tempmate and have been advised to stick it to the side of a longneck filled with water in my fridge beside the fermenters.

just wondering where fellow brewers place theirs? on the side of the fermenter or on another vessel like i have described?

it was explained to me something about thermal mass and thats where i switched off.........

cheers

 

[michael_aussie]

i have a tempmate and have been advised to stick it to the side of a longneck filled with water in my fridge beside the fermenters.

just wondering where fellow brewers place theirs? on the side of the fermenter or on another vessel like i have described?

it was explained to me something about thermal mass and thats where i switched off.........

cheers

Thermal mass is the efffect of the mass of an object providing "inertia" against temperature fluctuations.

In layman's terms this means there is enough mass around the probe so that the probe takes longer to heat up or cool down so is less effected by small fluctuations in temperature.

The down side of "thermal mass" is the probe is also less sensitive to actual temperature changes.

I think the thing that is often overlooked is your fermenter has more thermal mass than a longneck, so it in itself damps out temperature fluctuations.

I just dangle my virgin temperature probe in the fermenting fridge.



ooops.... did you tune out on my first line?????

 

[RickyC]

I have stainless steel tubular thermowells mounted directly in my fermenter via an extra hole in the lid with a grommet. This way you can get an accurate temperature measurement of the fluid in the fermenter and gain greater control, without the risk of infection if you where to drop the temperature element directly into the fermenter.

As you may know, the ambient temperature outside of the fermenter (in the fridge for example) can differ greatly to the temperature of the fluid in the fermenter. Theoretically you would need to place the probe in a similar body of fluid to measure temperatures close to that of the fermenter. So temp in a 750ml longneck would be different to the temp in a 23l batch when both placed in the same fridge, being switched on and off for temperature control.

Placing the temp element in the longneck of water simply dampens the temperature, as descibed by michael_aussie. However this will not give an accurate temp of the fermenter and not true control of the fermenter temp.

 

[OzBeer_MD]

If you don't want to go as far as RickyC, then tape the probe to the side of the fermenter (half way up the wort) and include some kind of insulation between the probe and the adhesive tape.

MD

 

[Banshee]

I place my probe in a glass or bottle filled with water.

 

[argon]

probe wrapped in a stubbie holder, strapped by elastic to the side of the fermenter... copes well with thermal lag

 

[kelbygreen]

mine is taped to 1" packing foam thats shaped to the curve of the fermenter with a groove cut in so the cable and probe are flush with the foam. then its tapes about half way up the fermenter as tight as i can to get a good seal

 

[OzBeer_MD]

I place my probe in a glass or bottle filled with water.

Well at least that water will be at the desired fermentation temperature :blink:

 

[kelbygreen]

well I have been told to put a bottle of metho with a probe in it to keep kegs at a good temp so guess that could work with a fermenter

 

[jakub76]

mine is taped to 1" packing foam thats shaped to the curve of the fermenter with a groove cut in so the cable and probe are flush with the foam. then its tapes about half way up the fermenter as tight as i can to get a good seal

I do a very similar thing. Recently have been using folded bubble wrap to insulate and an ocky strap to secure. I did try the tallie of water idea - in theory it's a good way to make sure you don't overshoot and get your wort too cold but I found that the tallie reached ferm temp in about 15 minutes while the fermenter full of wort could take 8 hours.

I recently had a massive overshoot while I had a bunch of beers packing the fridge around the fermenter. I had been lagering close to two batches of bottles at 4C and threw in a fermenter I was trying to cool down from 25 to 18. While the fridge stopped when the wort got to 18, the surrounding bottles of beer kept cooling the wort down to 16 before I realised and opened the door. Even with the door open it took around 32 hours before the temp of the wort crept back up to the 18 I was shooting for. Needless to say I pitched cold.

 

[amiddler]

I have 2 fermenters in my fridge that push very tightly against each other. I just poke the probe between the 2. Borrowed a fellow brewers Ph and temp probe and double checked wort temp Vs Mashmate temp and found wort was +2'C so just put an adjustment in the Mashmate. Close enough for where i'm at with my brewing without going full PID controler.

Drew

 

[Hatchy]

I can't wait to explain to my non brewing mates that I've got a complete lack of respect for my beer because I have the temp probe sitting on the floor of my fermenting fridge. I need a thermowell.

 

[felten]

Definitely strap it to the side of your fermenter, with something like an old stubby holder or some polystyrene as insulation against the ambient temp.

 

[Thirsty Boy]

If you tape the probe to the fermenter - because of the hysteresis of the controller, you are forcing your fermenter to cycle up and down through the full range.

So for instance, if you controller is set to 20 degrees and has a 1 degree range. It will go up to 21 before it turns on the fridge, and let it fall down to 19 before it turns it off. It so happens that the range on a template is more than that...

So, if your probe were in the fridge hanging in the air... It will drive the air temperature between 19 & 21 and hopefully average out at 20. Ignoring for a moment the heat generated by fermentation, your fermenter, with its much larger thermal inertia than the volume of air inside your fridge, will also cyle up and down hopefully averging 20, but over a much smaller range than the air mass. Giving you not only accurate control over your average temperature, but a small actual variation from hottest to coolest temp.

However - if you tape the probe to the fermenter. The controller switches the fridge on and drives the temperature of the actual fermenter down to 19 & then let's it warm up to 20. So while you are still averaging 20 - you are actually forcing your beer temp to sine wave over a range of 2 degree to do it.

Taping it to a bottle of water or whatever does the same thing, but less drastically.

Probe in the air will give you the most steady beer temperature, but will require you to ensure that the internal heat of the fermentation doesn't let it creep to high, and your fridge will cycle more frequently for shorter times.

Probe in a thermowell or taped to the fermenter will give an accurate reading, and you fridge will cycle less frequently but for longer times - but it will force your wort to fluctuate between the upper and lower hysteresis limits and your fernmentation temperature will not and cannot ever be steady.

I Vote probe hanging in the air of a fan forced fridge.

TB

 

[QldKev]

This has been discussed a few time before, and most likely a few time more; ask 3 brewers this question you will get 5 answers.

You are fermenting is a thermal mass that is exothermic.

In my opinion from what I have experienced in my brewery;
If you hang the probe free air, during the initial stages of fermenting, the wort will often be a couple of degrees warmer than the surrounding air. This will vary with the distance the probe is from the fermentor as air is a very bad conductor of heat. The more aggressive the yeast, the more this will become an issue.

If you put the probe in a jar of water, you may have a jar of water at the correct temp. Pitty about your wort, which is a larger thermal mass and is also exothermic . Therefore your wort may be warmer than the sample.

If you tape it to the side of the fermentor, and insulate it / use a probe into the wort. Then your wort is subject to the full swing of the temp controller. In this case I would set the hysteresis to 1, but at least you know the correct temp of the wort.

If you tape it to the side of the fermentor, and do not insulate it, you should get a balance of wort temp vs fridge air temp.

I have 2 fermentors in my fridge, probe stuck to the top fermentors un-insulated. I have actually measured during peak fermenting the bottom one warmer that the top one. Since coolness settles to the bottom of the fridge, this would not be expected. I can only assume that the top on being close to the cooling was exchanging the heat more effectively. I have added a 120mm pc fan to help aid in circulation and this has rectified most of the variation. This variation of temperatures within my own fridge shows that since air is not a good conductor I would not recommend either free air, nor using a sample water jar. Also if you hang your probe free air, I would ensure you have decent air circulation.

Ultimately which ever way you choose your beer is still within a temp controller environment, so will come out 100% better than a fermentor sitting on the kitchen table in the middle of summer. Think of the temperature swing that would see over a 24hour period.

QldKev

 

[Banshee]

Like mentioned above so many answers will be given. I would suggest going to your nearest micro brewery and asking/seeing how they get their temp readings. I have been to some and all they do is hold the fermenting vessels in a coolroom at a set temp with a liquid filled probe like the ones found in your common fridge. None that I know of, or come across so far stick a probe in the fermenter or tape it to the side of the vessel.
Go ask the professionals who sell it to us. :icon_cheers:

 

[Gopha]

Hi, This is how my temp controller is set up, hysteresis set at .5C. I also use a heater belt in the winter time linked to the same temp controller.
Currently cold conditioning an APA, temp set at 2C the fridge has just fired up, temp currently 2.4C - Cheers

 

[QldKev]

Like mentioned above so many answers will be given. I would suggest going to your nearest micro brewery and asking/seeing how they get their temp readings. I have been to some and all they do is hold the fermenting vessels in a cool room at a set temp with a liquid filled probe like the ones found in your common fridge. None that I know of, or come across so far stick a probe in the fermentor or tape it to the side of the vessel.
Go ask the professionals who sell it to us. :icon_cheers:

Yep, check out any micro breweries. I don't know exactly what they do; I only know what has been tested in my setup. Take all details into consideration. Do they have a temp correction for the initial fermenting periods? ie, ferment 2 degrees cooler?/do they ferment using multiple temperature stages?. Do they have different temperature depending on beer and yeast used? Maybe more aggressive yeasts, say for a wiezen, they may drop 1 or 2 degrees on the thermostat? Obviously different yeasts need different temps, but how exact are we at home for temperatures with all our different yeasts?


Do they have a reasonable turnover of air, most commercial cool rooms do?
From my earlier post
"Also if you hang your probe free air, I would ensure you have decent air circulation." I think air turn over solves most problems with equalising temperatures.



QldKev

 

[drew9242]

I have 2 fermenters in my fridge that push very tightly against each other. I just poke the probe between the 2. Borrowed a fellow brewers Ph and temp probe and double checked wort temp Vs Mashmate temp and found wort was +2'C so just put an adjustment in the Mashmate. Close enough for where i'm at with my brewing without going full PID controler.

Drew

Hehe Must be either a WA or a Drew thing. Because i do the exact same thing. I reckon you get the best of both worlds, bit of the air temp and some of the heat that the fermentation is producing. I Just set it to 17 and it sits at 18 beautifully.

 

[beerDingo]

I just put the probe against the fermentor and use some yellow tack to hold it there.

Good point from TB about the fermentor swinging across the entire range. However, if the fridge/heater don't come on very often, then I spose lowering the range should fix some of those problems. So .5 degree or lower on eaither side should still stop the fridge from comming on as often as free hanging in the air. I will have to look in to it.