Temperature Probe placement

[roosmur]

I have a STC-1000 controller and a refrigerator which I use as a fermentation chamber. I also use a "brew-belt" around my glass carboy as the heating source.

Sanitation aside, what is the forum's view on placing the temperature probe from the STC-1000 into the actual fermenting wort? I have tried before placing the temp probe into a beaker of water in the fridge, (because the air temp and liquid temps are different if there is thermal activity), but appreciat that due to the exothermic nature of fermentation, the wort temperature will be a few degrees warmer than the water beaker (especially during very active fermentation). Given the tight-ish range we are trying to ferment in, "a few degrees warmer" is indeed quite a difference.

People have talked about "cycling" being the disadvantage of placing the probe directly in the beer. If you set the STC-1000 to a 1 degree window and impose a 3 minute delay override between heat and cool, is cycling a problem?

Why doesn't everyone just put their probes straight into the wort?

 

[FatDragon]

You say "sanitation aside", but that's the issue right there. Taping the probe to the side of the fermentation vessel, insulated from the air temperature with some kind of foam, will report temperatures as accurately as you need, without any added possibility of infection.

 

[Teromous]

Taping the probe to the side of the fermentation vessel, insulated from the air temperature with some kind of foam, will report temperatures as accurately as you need, without any added possibility of infection.

This is what I do.

Ideally you would want to use a thermowell, but work with what you have right?

 

[roosmur]

Thanks Guys - I did use to tape my probe to to the side of my glass carboy, ten stopped doing this. I guess a well insulated patch over it to ensure it only reads the glass temperature is probably fine.

 

[MrHopScotch]

Insulated on the outside should be fine. That's what I do. Tape the probe on and tape a layer or two of bubble wrap on top of the probe.

Though I've never personally had a problem with it, I have heard that you should be careful using a heating belt on glass carboys because the thermal stress from heating a small area could weaken/break them. I use a fermwrap to avoid this. It's not much more expensive and worth the peace of mind for me.

 

[betarhoalphadelta]

I think ideal is a thermowell in the center of the mass. But taped on the outside with some insulation is close enough to make great beer.