Fermentation fridge temperature control

[Keruso]

Apologies in advance for a really daft question but here goes...
I have a STC1000 temperature control system, brew belt and a fridge where I ferment mostly IPAs so tend to set the temperature at 18c. I have used sticky tape to stick a couple of layers of bubble wrap to the FV which makes a chamber that I push the probe into. There’s still a bit of an air gap as the probe isn’t stuck firmly to the Plastic FV. I noticed today during dry hopping that when I hold the probe tight to the FV the temperature was actually 21c not 18c so bubble wrap isn’t an effective way to hold probe. Do you have a tried and tested method of keeping the probe in close contact and insulated against the FV ? Thanks.

 

[RichardM]

How did you hold the probe tight to the fv? If was with your fingers was the temp rise you saw body heat?

 

[Keruso]

How did you hold the probe tight to the fv? If was with your fingers was the temp rise you saw body heat?

Hi, I just pushed the probe close by pressing down over the bubble wrap so I don’t think it was body heat. I wonder if foam or a sponge or similar would be better ? Just thought I would ask as I’m sure people have better ways.. thanks

 

[RichardM]

Just use plenty of gaffer tape over the bubble wrap to press it down

 

[stz]

Three ways to approach this ..

- Devise a perfect method to accurately read the temperature of the exterior of the vessel...
- Measure the internal temperature of the fermenting wort...
- Let your taste buds and experience guide you ...

The first is useful if you don't trust yourself and you want an accurate as possible start point. The internal temperature is often a few degrees higher than the external. The second will teach you what to actually set it to, maybe you need to set it to 18C to get an internal temperature of 21C? The third has the benefit of being absolute, if you are trying to get a yeast to express esters and you don't get them go warmer, who cares if it says 21C or 25C as long as the beer tastes how you want?

Personally I'm happy with taping it to the side of the vessel at home and setting it on the low side. If I want a maximum temperature of 23C I set it to 21C. 21C and I set it to 19C. I've measured and I'm happy my taste buds are sufficiently calibrated. I fall into the camp of controlling temperature during the initial stages of fermentation and allowing free rise and fall at points to finish beer in an energy efficient manner. I rarely wish to use heating to maintain a temperature, setting a max and using insulation works for me, commercially don't even have heating though we have thermowells.

In the past I've placed a square of bubble wrap over the probe and taped it to the side. This made it a little closer to the internal temperature, but I don't need it to be closer, I just need to know how far off it is!

 

[Keruso]

Three ways to approach this ..

- Devise a perfect method to accurately read the temperature of the exterior of the vessel...
- Measure the internal temperature of the fermenting wort...
- Let your taste buds and experience guide you ...

The first is useful if you don't trust yourself and you want an accurate as possible start point. The internal temperature is often a few degrees higher than the external. The second will teach you what to actually set it to, maybe you need to set it to 18C to get an internal temperature of 21C? The third has the benefit of being absolute, if you are trying to get a yeast to express esters and you don't get them go warmer, who cares if it says 21C or 25C as long as the beer tastes how you want?

Personally I'm happy with taping it to the side of the vessel at home and setting it on the low side. If I want a maximum temperature of 23C I set it to 21C. 21C and I set it to 19C. I've measured and I'm happy my taste buds are sufficiently calibrated. I fall into the camp of controlling temperature during the initial stages of fermentation and allowing free rise and fall at points to finish beer in an energy efficient manner. I rarely wish to use heating to maintain a temperature, setting a max and using insulation works for me, commercially don't even have heating though we have thermowells.

In the past I've placed a square of bubble wrap over the probe and taped it to the side. This made it a little closer to the internal temperature, but I don't need it to be closer, I just need to know how far off it is!

Great advice thank you, I want to get the most accurate reading I can as i'm aware how temperature affects yeast performance. I'll try one of those washing-up sponges placed over the probe and tape it quite tightly, and use a thermometer to see what the difference between the actual FV temperature and the STC1000 display is and adjust accordingly.

 

[Bigcol49]

Hi!
Bungee cord applies more pressure than tspe.

 

[BarnBrian]

Great advice thank you, I want to get the most accurate reading I can as i'm aware how temperature affects yeast performance. I'll try one of those washing-up sponges placed over the probe and tape it quite tightly, and use a thermometer to see what the difference between the actual FV temperature and the STC1000 display is and adjust accordingly.

If you want to go really over the top you could use Thermal Grease as well.

 

[Drunkula]

Big wad of blu-tak. It also provides some thermal inertia. You could also put the sponge/wrap over the top of it.

 

[Dutto]

I'm a firm believer that what I am trying to control is the temperature of the wort and not the temperature of the fridge!

To achieve this, the probe is insulated from the temperature in the fridge by means of an ordinary kitchen sponge with a notch cut in to it so that the probe is tight up against the side of the FV.

The sponge and probe are then held against the side of the FV by wedging them underneath the FV's handle.

Simple!