More Accurate Fermenter Temp Than Stick On Digi Thermometer?

[Braeden]

I am new to homebrewing (not homebrew drinking) having just bought an off the shelf coopers beer kit.

My second concern (with the first being the dodgy/generic yeast, sugar, etc and instructions it comes with, but I can work most of that out with some reading and careful buying for future brews) is the stick on digital thermometer. I would like a more accurate measure of temp from the fermenter. At this stage I don't have a fridge or other method of insulating/cooling the fermenter from ambient air temp, so a more accurate reading won't be overly beneficial given that I'm simply going to wrap it in a wet towel if its too warm... Regardless, this is something I can afford to do now and will have use for in the future.

Some quick googleing led me to this DIY temp sensor: http://martybugs.net/electronics/tempsensor/hardware.cgi

(The above pictured sensor can be made to read temps from more than one sensor along its length)

What I am aiming for is a single cable with one sensor outside the fermenter and another inside submerged in the wurt, probably through a second rubber grommet like the airlock one.

With such a setup hooked up to a comp in the downstairs brew room I will be able to monitor ambient and brew temps from upstairs.

My concern with this idea is food / beer safe waterproofing for the section of cable that will be inside the fermenter. Is there a readily availiable silicone, epoxy or heatshrink that will be food safe, waterproof, easy to sanitize and not impart any taste to the beer?


Cheers for any input

 

[Pete2501]

I'm in the same boat of temp monitoring and will be looking to this baby for all my temperature needs. For $50 I'm a happy man.

I'm getting a chest freezer as well though so I might have to get two. One for the fridge and one for the chest freezer. It ticks all the boxes of taste and sanitising.

Edit: reasoning


​

 

[drsmurto]

IMO - the stick on thermo isn't too bad.

If you cant control the temp of your fermentation then i wouldn't go all out to build something just to have a slightly more accurate picture of what said uncontrolled fermentation temperature is.

Spend time/money/effort in getting a way of controlling the temperature.

A dead fridge is an insulated box which is a good start. A heat belt/pad for winter, frozen 2L water bottles in summer.

 

[technocat]

I am new to homebrewing (not homebrew drinking) having just bought an off the shelf coopers beer kit.

My second concern (with the first being the dodgy/generic yeast, sugar, etc and instructions it comes with, but I can work most of that out with some reading and careful buying for future brews) is the stick on digital thermometer. I would like a more accurate measure of temp from the fermenter. At this stage I don't have a fridge or other method of insulating/cooling the fermenter from ambient air temp, so a more accurate reading won't be overly beneficial given that I'm simply going to wrap it in a wet towel if its too warm... Regardless, this is something I can afford to do now and will have use for in the future.

Some quick googleing led me to this DIY temp sensor: http://martybugs.net/electronics/tempsensor/hardware.cgi

(The above pictured sensor can be made to read temps from more than one sensor along its length)

What I am aiming for is a single cable with one sensor outside the fermenter and another inside submerged in the wurt, probably through a second rubber grommet like the airlock one.

With such a setup hooked up to a comp in the downstairs brew room I will be able to monitor ambient and brew temps from upstairs.

My concern with this idea is food / beer safe waterproofing for the section of cable that will be inside the fermenter. Is there a readily availiable silicone, epoxy or heatshrink that will be food safe, waterproof, easy to sanitize and not impart any taste to the beer?


Cheers for any input

I would suggest a thermowell made of stainless steel so it is either fixed to the lid of your fermenter or a tight fit through a rubber grommet set in the lid similar to the airlock. The TO92 package is around 4-5mm across so it would fit a 6mm Beerbelly thermowell or S/steel tubing of the same size seal at one end. Out of curiosity what software are you running to accommodate this setup.

 

[Rod]

I'm in the same boat of temp monitoring and will be looking to this baby for all my temperature needs. For $50 I'm a happy man.

I'm getting a chest freezer as well though so I might have to get two. One for the fridge and one for the chest freezer. It ticks all the boxes of taste and sanitising.

Edit: reasoning


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The fridgemate is the way to go ,

you may adjust your brew to the correct temperature , but this not much good if you cannot control the temperature during the fermentation

for ales you will need low twenties.

Hook it up as per instructions and plug the fridge lead into the unit and away you go , the fridge mate will keep your brew within a couple of degrees

during the summer you cannot be without one to keep your brew @ low twenties when the room temp is above 26C

during the winter it will control your heat pad or belt when the room temperature is about 14C and you want to make ales

of course for lagers you will need the temp to be about 12 to 14 C and can make then in the summer




put the probe onto the side of the fermenter with some blue tac and you will see the temperature at any time

 

[Braeden]

Thanks for the replies,

DrSmurto, I will have to have a hunt around some local 2nd hand stores / trading posts and see if I can find something ideal. Tinkering with a temp sensor setup for remote monitoring is something I will enjoy almost as much as brewing the beer itself, even if the end result is no where near as beneficial

Cheers for the info Beernut, one of them would be ideal bar that I don't think it will reach the fluid level from the fermenter lid, but that's an easy fix. Or just s/steel tube as you said.

As for software I will be using no doubt the linux version outlined on http://martybugs.net/electronics/tempsensor/software.cgi, windows version is at http://martybugs.net/electronics/tempsensor/software2.cgi

That coupled with a webserver running on any old box I have laying around and a wireless card thrown in and I think I should be able to hack together something to spit out a live feed to a dynamic webpage.

 

[randyrob]

Hey Braeden,

i've made something simular and just duct tape one sensor to the fermenter and the other hangs about in ambient temp.

There is no need to submerge a sensor inside the fermenting wort, besides adding another spot for nasties to hide

the temperature doesn't vary greatly from just having it strapped to the side.








Rob.

 

[Braeden]

Cheers randyrob, looks like your setup deals with a little more than temp sensing ( switching heater / cooler on/off to attain target temp). Is that running over a serial port or other? Is that using software you cobbled together yourself or something ready made for this kind of thing?

 

[randyrob]

Cheers randyrob, looks like your setup deals with a little more than temp sensing ( switching heater / cooler on/off to attain target temp). Is that running over a serial port or other? Is that using software you cobbled together yourself or something ready made for this kind of thing?

Hey Mate,

It can easliy do just Temperature Monitoring if that's what your after.

It uses a cheap standalone microcontroller (arduino) to control and monitor temps and feeds back information to the computer (in my case via serial but you can also use usb, ethernet, bluetooth, wireless etc)

I've opensourced the project and the code is available on my website.

Rob.

 

[Braeden]

Cheers Rob,

Looks like a pretty sophisticated setup you have there

The more I look at it the more I like the idea of an Arduino board or similar to give me more control over whatever I decide to add to the system in the future.

Thats given me a bit to think about, thanks for all the info and the work you've done making and sharing your project.

 

[zagadka]

i've made something simular and just duct tape one sensor to the fermenter and the other hangs about in ambient temp.

I'd better jump in with what I'm working on too :icon_cheers: Those look good! I've been meaning to buy an Arduino to play with.

It's currently only monitoring...


Control Box.


A graph showing blue cool, green idle, red heat.


Mine is parallel port based for control with the same DS18XXX sensors on the serial that you are using for sensing. I'm currently using an old 1U P3 server to run it because it pulls under 90W.