Inkbird temp probe placement

[Andyglanville]

Hi guys! New to the forum and to home brewing in general!
Iv just finished getting all my kit together to start some cider kits - Iv bought a heat pad and an Inkbird temp controller-just wondering how and where people normally position the temp probe? Seen some people saying that they stick it to the outside of the FV, but I can’t see how this would give an accurate reading (I work in pharmaceutical production and QA which probably doesn’t help lol )

TIA

Andy

 

[Drunkula]

I use a big lump of blu-tak fold it over a few times, put the probe on one side and then mash that against the side of the fermenter. If you think about the thermal mass of the fermenter (liquid) vs temperature variations outside (gas) then the liquid side is always going to be far more stable and reprasentatatative(!?) of the fermentation temperature, which is actually the thing you want to control. Right now I've got a ferment going and the fermenter is reading 19.3c and an ambient reading in the freezer is 18.6. Some people put a glass of water in the fermenter and put the probe in that but it's not reprasenta...something of the fermentation temperature.

Some people tape the probe to the side then put a heap of bubble wrap over it but I think the blu-tak works better and has its own thermal mass that's more like the fermenter. I might open it to do some tinkering and the ambient sensor today went up to 26 but the ferment sensor only 19.2.

EDIT: It's the fermentation temperature you want to measure, not the container's.

So anyway, that's my thinking.

 

[110ben]

I agree with @Drunkula. I have some foil backed bubble wrap which came in an m and s hamper. I tape this over the probe and on the side of the fv which works for me

 

[Bigcol49]

Hi!
Bungee cord holding the probe on the outside of the FV beneath a kitchen sponge/scouring pad.

 

[Graz]

I'm also of the school of taping it to the outside with bubble wrap over the top. That's in a brew fridge though and I want the controller to be reacting to the actual temperature of the beer rather than the air inside the fridge. I suspect the absolute best method would be to put the probe in the liquid inside the FV but I didn't really want to do this for hygiene reasons so I see the bubble wrap method as a good compromise.

 

[Andyglanville]

Thanks for the replies, some good solutions and ideas to consider.
One possibility that had crossed my mind so far was to fit an adjustable cable gland into the FV lid, so that the temp probe could be submerged in the brew (after sterilisation of course) and that lid still airtight.

https://www.amazon.co.uk/dp/B01IONEL8G/?tag=skimlinks_replacement-20

 

[BeerCat]

Thanks for the replies, some good solutions and ideas to consider.
One possibility that had crossed my mind so far was to fit an adjustable cable gland into the FV lid, so that the temp probe could be submerged in the brew (after sterilisation of course) and that lid still airtight.

https://www.amazon.co.uk/dp/B01IONEL8G/?tag=skimlinks_replacement-20

I have tried this using a thermowell and i found the temp matched exactly when taped on the outside so i don't bother.

 

[GerritT]

Outside advantage: less chance of infection.

 

[rank_frank]

I've got a thermowell fitted in the middle of the lid of my FV. It's fine for normal fermentation but for lagering I found that the middle of the beer and the outside are at such a different temperature that I got a layer of ice building up around the edge of the beer whilst the middle was still at 2 or 3C.

 

[Meza]

Thanks for the replies, some good solutions and ideas to consider.
One possibility that had crossed my mind so far was to fit an adjustable cable gland into the FV lid, so that the temp probe could be submerged in the brew (after sterilisation of course) and that lid still airtight.

https://www.amazon.co.uk/dp/B01IONEL8G/?tag=skimlinks_replacement-20

I use a gland like this through the lid on my FV. It works really well. I'm controlling temps with Fermentrack and BrewPiLess, which has inputs for beer-temp, chamber temp and room temp.

You have to use a really small gland to get a good tight grip on the narrow cable. I also used some plumber's jointing compound (like putty) on the gland threads to get an airtight seal. Without this the airlock didn't bubble.

 

[Ghillie]

Hi!
Bungee cord holding the probe on the outside of the FV beneath a kitchen sponge/scouring pad.

The exact same process here too!

 

[Tunabeast]

I'm glad this thread has come up: my old set up was a plastic fermenter where I inserted the inkbird temperature probe directly into the liquid, through a glanded hole in the lid. For Christmas I was lucky enough to receive a shiny stainless fermenter and I have no intention of making a hole in the lid for the probe.

Interested to hear more folks methods of measuring temperatures from the outside, do you have any photos of your setups?

 

[pottsworth]

I had a fermenter for a while that took a bung with an airlock in it, so used that to achieve a similar result.

I froze a bung, drilled a second hole that the probe just fit through (after a healthy amount of lubing up), then wrapped electrical tape around the cable above the bu to make it thick enough to seal the hole, so the metal end hung in the middle of the beer.

I now have a small and medium fast ferment though, which both have thermowells, which are much easier.

 

[CD]

I drilled a 3/8" hole through the side of my s/s cylindriconical FV near the top, pushed a piece of pvc tubing through with a sawn off s/s bolt (no thread) sealing the end, and the probe is fed down the tube. Bolt acts as a weight so probe is well under the surface. Never had any problems.

 

[CeeGee]

Hi!
Bungee cord holding the probe on the outside of the FV beneath a kitchen sponge/scouring pad.

Another kitchen sponge fan here, but I use gaffer tape to hold it on. Works just fine!

 

[DCBC]

One thing to remember is that the movement of the liquid, aided by the stirring effect of clumps of yeast within the fermenter, means that the heat gets dispersed very quickly and evenly. So it's not much cooler at the edge than the centre during active fermentation. This is another reason why the insulated probe on the outside is near enough to what you need.

 

[John Holgreaves]

Just dangle the probe into the wort, the lid traps the wire.