dual temp jacket controls

[billk]

We just installed 4 used fermenters that have separate jackets for the cone and the body. Is there an advantage to having two separate thermostats per tank, or is it design overkill and I would be better off saving the money and only installing 1 per tank? The tanks I have now only have one jacket and I can't think of a situation when I would need to be running two different temps in the same fermenter.

Thanks,

Bill

[BMOOR]

Chances are you won't have to set the temps differently, but I see two advantages to this set up:
1) it's nice to know the temp in your cone. If you have a big amount of yeast there under the beer, it can produce quite a bit of heat, even though the beer is cold.
2) if you are working up yeast and only have a slurry in the cone, you can just turn on the cone jacket and not the body jacket.

[Jephro]

I have worked with dual zoned Bohemian FV's and noticed many times, mostly during primary, a 2-3 degree F difference form the top and bottom thermistors. As we all know heat rises, i think it does keep a more constant temp. Well that is as long as you are running separate glycol lines and solenoids to each jacket. I guess all things considered it's nice, but not necessary if you don't want to spend the money on extra equipment you can just jumper the jackets together.

Jeff

[NYSBrewer]

I think size matters!! If you have a much larger tank, with a larger cone, meaning more yeast, more heat, it mightg make sense. A seven or even a fourteen barrel fermenter can get away with one jacket. If it is an 80 barrel...maybey it will benifit. Any more thoughts?

[BelgianBrewer]

Reason

If the temperature probes are on different height levels, the goal of the design might have been to make sure on of the probes is always in the liquid.
From a design standpoint you typically want the probe on the cylindrical part of the tank, in the cold zone during fermentation. But when brewing a half batch, the probe still needs to be in the liquid in order to register and control your glycol glow. At that moment 2 probes might be useful, but it will make your control panel a lot more complex.

BelgianBrewer

https://www.sbmbrew.com

[billk]

This is for a 10 bbl system so the max capacity on the tanks is only 12 bbls. With the design of my kettle the smallest batch I can brew is 8 bbls, so both temp probes are going to always be submerged. I didn't think about yeast propagation, maybe I'll keep one tank on separate controls for that purpose.
Thanks, any other feed back is appreciated.

Bill

[gitchegumee]

I subscribe to the KISS theory. For a 10 bbl unitank, you don't need two separate cooling loops--even for yeast propagation. Two loops are difficult to harmonize with an on-off circuit. You'd likely overcool during fermentation and I can't think of any benefits. What I would do is to use a large glycol header and split the flow to the two jackets after the solenoid valve. As far as yeast propagation goes, you're only talking about 1 bbl of wort, a small volume with lots of surface area. Propagation is often done at slightly elevated temperatures, and the heat transfer from the wort to the ambient should keep your yeast from getting too warm.

[Moonlight]

If you have an extra sensor, run both sensor wires into the thermostat and if you're curious about the cone temp, just swap wires with a screwdriver. I totally agree that if it is plumbed to run both jackets in parallel, the cooling surface on the cone to its cone volume may be higher than the same ratio for the tank body, and you could over-cool the cone during fermentation. If there was a valve in line to the cone only. some trial and error could determine how much to close it and match the cooling rates between jackets. Or heck, just ignore cooling the cone until you want to crash and protect the settling yeast as that is when cone cooling is most critical.