FV cooling, outer coil or inner submerged?

[jat147]

Hi,
If you were a greedy brewer and had designs on a new FV that was too big to make a cabinet to fit the thing in to, how do you think would be the best way of getting your cooling achieved? I guess the two options are (a) wind copper around the FV, cover with insulation and then pump coolant around it. (b) fit a submersible cooler to the inside of the FV, like this: http://www.winegrowers.info/wine_equip/ ... plates.htm

The submersible option isn't cheap, but then again copper tube isn't either. So, even if the costs were similar, which would be more effective?
I'm thinking that the external coil is the more sanitary option, but way more difficult to install. Anyone had experience of this problem?

[gregorach]

You don't have to use copper... I cool my FV with several metres of 1/2" plastic tubing coiled around the outside. Took about 15 minutes to install, works just fine. I pump cold water from a picnic cooler, which I keep cold with 1L PET bottles 3/4 full of water which I freeze in the kitchen freezer. The pump and heating belt are driven by a PID, and it's currently holding my Pilsner at 12.0 C (+/- 0.1) very nicely thank you.

[Blackaddler]

Here's a couple of pics of my FV... one in this thread and also this.

There's no reason that you couldn't use plastic beer line instead of copper. It's be easier to coil around the FV, and cheaper too, I expect.

I loosely based my design on commercial ones I'd seen.

[jat147]

Yeah thanks chaps, you're quite right - the expensive of copper coiled around is just not needed. In which case the sumbersible option is rather more expensive after all, but I cant help feeling that it could be more effective on bigger volumes? I'm hoping to not shut down all brewing this summer for a change.


500mm x 330mm is £155. I'm thinking about crash cooling, and can see this working pretty well if I can pump glycol through it?

Dunc, how low can the hose option get you to - on what volume?

Many thanks again

[barneey]

If it helps, Ive been thinking of the same problem.

Outer coil = no cleaning.

Inner coil = cleaning specially with a coil (would need to stainless) + try looking for stainless pipe more than 3 m long.

The only other alternative i am looking for is this one

Cheers

[gregorach]

Dunc, how low can the hose option get you to - on what volume?

Well, I'm currently only brewing 20-22L lengths, but the limit is really set by the volume of coolant, the temperature you can get it down to, and the thermal conductivity of the beer. I could certainly get down to ~10 degrees easily enough during active fermentation whilst only swapping out 2 bottles of ice twice a day. I don't crash cool so I've never tried getting it any colder, but with enough ice and enough insulation, I'm sure it could be done. If you had a proper chiller I don't see why you couldn't get it down to lagering temperatures if you wanted, although condensation might become an issue depending on the location. As for the rate at which you can cool, that's probably going to be limited by the thermal conductivity of the beer itself. With a really cold reservoir, I can cool at anything up to 1 degree per hour - and I could easily improve that by using a longer cooling coil. It's far more efficient than using a fridge.

[jat147]

Thanks Dunc thats really useful.

Sorry I missed your thread Barneey, looks like there is always someone scratching their head over the same problem as you?

[Kev888]

I've also found the inner vs outer question a conundrum, essentially because they both work so theres no clear winner. I'm probably going to go with outer to make cleaning easier, but actually if the immersion element went in through the lid i doubt there'd be a lot in it, as you could then take the pot away without having to disconnect the cooling lines.

If you are interested in immersion then you can get long stainless coils like these

Cheers
Kev

[barneey]

The only trouble I can see with the cornelis ones is the cleaning aspect of the things, as they are quite tightly coiled, that, and they may not sit too far into the liquid without further pipe extensions, personally wouldnt want a joint inside the vessel, just incase it leaked (paranoia), hence I thought about caldding the coil etc, then aleman came up with a simplier more cost effective idea welding skills required tho.

[boingy]

Anyone know if you get any long term corrosion effect if you have copper in contact with stainless?
It's usually a bad idea to allow two dissimilar metals to be in contact with each other.

[Kev888]

The only trouble I can see with the cornelis ones is the cleaning aspect of the things, as they are quite tightly coiled, that, and they may not sit too far into the liquid without further pipe extensions, personally wouldnt want a joint inside the vessel, just incase it leaked (paranoia), hence I thought about caldding the coil etc, then aleman came up with a simplier more cost effective idea welding skills required tho.

Yeah, I know what you mean, but I guess it depends on the size of your pot. I believe some people have distorted and stretched out the spirals into a tall 3d conical spiral, but I've just been looking and can't seem to find the posta I've seen in the past. I did find a post of yours though here in which beer taster usefully gives some sizes. When I bought my cooler I was surprised at how big they were!

Anyone know if you get any long term corrosion effect if you have copper in contact with stainless?
It's usually a bad idea to allow two dissimilar metals to be in contact with each other.

I've only 'gone stainless' in the last few years so can't testify in practice, but copper is pretty close to stainless's adonic index so galvanic corrosion should be fairly low. Copper's index is 0.35v, whilst chromium steel is about 0.5v; a 0.15 differential is said to be acceptible for harsh environments - not sure how harsh an FV would be though..

Though don't assume I'm any sort of expert here - I stumbled on this info on wikipedia not long ago when deciding if brass would be okay instead of stainless skin fittings - I decided it was, but perhaps not so good for some of the acid cleaners i was intending to run through it on route to the plate chiller.

Cheers
Kev

[barneey]

Well I`m finally going to take the plunge and go for both a submerged unit (forum welder dependant ) and the outer coil pot design. Quite like the idea of Duncs frozen bottle design as a coolant source, after all who doesnt have a freezer on 24/7, if that doesnt work I always have a maxi beer cooler or my coil freezer.

Will let you know how I get on... might take a while tho

[Goulders]

Strongandco on YouTube uses an immersion cooler and beer engine (CLICK)[see about 5 mins in[. I think it may be Chris who used to provide a lot of advice on the forum.

I quite like the idea as I have no room for a fermenting fridge but the idea doesn't seem cheap.

[Scooby]

I use a product coil and recirculation from an under bar chiller. just needed a little stretching and bending. There is a thermowell
near the bottom of the fv for the temperature probe. I heat with vivarium mats round the outside of the fv, that's the reason I went for
an internal cooling coil. Both are controlled by a TC10. Never had a problem cleaning and it will drop 50l to 3C easily.

[Kev888]

Ah, I think that's the one I was dimly remembering - quality job!!

The more I think on this, the more I like the idea of the FV being removable from the cooling lines/lid, and those pictures help to convince me more. I think its going to come down to if my FVs are fixed in place or not.

Edit: I also just remembered this post, presumably using a coil from a remote cooler rather than a shelf cooler as it looks huge:

The product coils can clearly work, then!

Cheers
Kev