Cold Plate

[andrewg1978]

Hi All,

I am just starting out and looking at building my own magic box rather then pay big $$$ for rubbish.

1/ Materials - I have spoken to many people about the pipe is copper/aliminimum ok

2/ Pipe length and diameter - again many different views coil vs cold plate

Any help is much appreciated

 

[geoff_tewierik]

Grab this:

http://cgi.ebay.com.au/As-NEW-2-port-Cold-...emZ170187220003

Stick it in an esky, attach appropriate tap of choice, obtain gas of choice/regulator and attach to keg, Attach keg to plate, fill esky with ice.

And away you go.

 

[andrewg1978]

Grab this:

http://cgi.ebay.com.au/As-NEW-2-port-Cold-...emZ170187220003

Stick it in an esky, attach appropriate tap of choice, obtain gas of choice/regulator and attach to keg, Attach keg to plate, fill esky with ice.

And away you go.

Thanks for this, what I was really looking for is if copper or aliminimum pipe is acceptable for the coil or does it flavour beer. The one on ebay looks good but it is smallish, I have a large esky and I would assume the longer the pipe, the better.

Thanks
Andrew

 

[HKS]

I've been looking at building my own magic/miracle/jockey box as well re: below thread
http://www.aussiehomebrewer.com/forum/inde...19355&st=15

I was looking to go the stainless coil route. However I've pretty much decided to just go for a cold plate.

As for using copper coils:

At home I have copper coils submerged in glycol, and that works an absolute treat!

Andy

Me personally, I wouldn't use copper or aluminium, but that is just me and my stainless fetish.

The other thing about coils vs cold plates is. The coils are recommended to be in a ice/water bath whereas the cold plates its recommended that water is periodically drained away and to push down on the ice to stay in contact with the cold plate. I think it would be harder to maintain the ice/water bath than simply ice only.

Let us know what you end up deciding on, I'll certainly be interested.

Cheers

 

[Simon W]

Copper is the second best conductor of heat, followed by aluminium. The best is silver(slightly better than copper) but I'm guessing your not going to be buying any silver tubing! Stainless is not a good conductor of heat.
Why is this important? It affects the size and length of tube you will need.
You can get by with 'x' amount of copper coil, or twice as much aluminium coil, or much much much more stainless to cool the same amount of beer in the same amount of time.

Copper is apparently not good in contact with acidic beer, thats why it's not used for fermenters(it also kills yeast), but for the relatively short time it's in contact with the cooling line it might be ok.
Aluminium tube is probably not likely to be easy to coil, just a guess tho coz I've never tried it.
Aluminium has been linked by some to Alzheimers, tho at the cold temperatures and short contact time, I probably wouldn't worry.
Stainless is the easiest to keep clean.
Copper will oxidise if not used for a while and will need to be cleaned(hot acetic acid - vinegar) before passing beer through it. Beer will clean it slowly, but I wouldn't drink it.

 

[geoff_tewierik]

Aluminium has been linked by some to Alzheimers.

Debunked as a myth:

http://www.alzheimers.org.uk/site/scripts/...p?documentID=99

Would have no problem with copper (great for cold transfer), aluminium (almost as good as copper in transfer of cold) or stainless (easily cleaned out)

I'd be more likely to get a cold plate then a coil though, simply because they're more compact, thus uses a smaller esky.

Have never seen a cold plate vertical though, which would mean more of it was in contact with the ice, rather then sitting in a pool of ice water on the flat bottom of the esky. Anyone hazard a guess as to why?

 

[Simon W]

Yeah, thats why I said 'some', never believed it myself, but figure it's best to let people know the claims and they can make their own mind up.

Anyone hazard a guess as to why?

Cold icewater conducts heat better than ice+air.

 

[geoff_tewierik]

Yeah, thats why I said 'some', never believed it myself, but figure it's best to let people know the claims and they can make their own mind up.

I find it's easier to provide info and let them make up their own mind rather than feed the myth

Cold icewater conducts heat better than ice+air.

Fair enough.

 

[Simon W]

Some thermal conductivity(k) figures might help you decide what materials to use:

Silver 429
Copper 401
Aluminium 250
Stainless 16
Ice 2.18
Water 0.58
EPS (Foam) 0.03 (expanded Polystyrene)
Air (still) 0.024

k = W/(m.K)
All at 25oC except Ice.
Source.

 

[MHB]

Copper, Aluminium and I suppose Silver would be better thermally than stainless. The problem is that beer is acidic and attacks both Copper and Aluminium (I have no personal experience with solid silver heat exchangers and would only be guessing).

In the case of copper, I have seen several attempts made at copper coils; they all made the beer taste like old 2c pieces.

Anyone seen an old Aluminium beer keg?
I have a regular procession of old party kegs coming in - they are often pitted or corroded through, or full of that lovely white fuzzy stuff you get on old Aluminium whare.

The really important feature about the miracle plates is that the large lump of Aluminium acts like a thermal capacitor. The rate of thermal transfer between solids is much faster than from solid into a liquid.

The Aluminium block is cooled to the temperature of the ice water (~0C), when warm beer flows into the coil; the heat is lost through the thin wall of the stainless steel pipe into the Aluminium heat sink - very quickly - then dispersed into the ice water more slowly.

The coil is designed to hold more than a standard drink - so the incoming warm beer displaces pre-chilled beer.

I have used both and the plates beat any coil I have seen hands down.

As to the ice/water question - they work best when the plate is surrounded by water with the ice floating above it. Heat added to the water is transported up to the ice by convection, rather than just conduction.

MHB

 

[HKS]

As to the ice/water question - they work best when the plate is surrounded by water with the ice floating above it. Heat added to the water is transported up to the ice by convection, rather than just conduction.

MHB

See this is what I have experienced personally with every keg show I've done. Wake up the next morning and finish off the beers the other ******* should have drunk. Open the lid and there is water down the bottom with ice floating on top, and brr its cold and seems to work better than what the text suggests you should do, ie is drain the water.

I wonder who talked me into going for a cold plate instead of a coil.

 

[fungrel]

2

See this is what I have experienced personally with every keg show I've done. Wake up the next morning and finish off the beers the other ******* should have drunk. Open the lid and there is water down the bottom with ice floating on top, and brr its cold and seems to work better than what the text suggests you should do, ie is drain the water.

I wonder who talked me into going for a cold plate instead of a coil.

A 7 was s l8 l8 2rgi8cj,eggs

 

[Pnutapper]

Bit of Narco here, but since the strange bump above, I thought I would read the thread, and add my opinion. A few of the members here have asked me offline about this topic

I have had a couple of guys ask me about whether it is best to drain water or leave it in when using an ice chill plate. I have learnt a lot from the posts @MHB has made on various topics since joining this forum and completely respect his knowledge, but in this instance I must disagree with this post from a few years ago:

As to the ice/water question - they work best when the plate is surrounded by water with the ice floating above it. Heat added to the water is transported up to the ice by convection, rather than just conduction.

MHB

I often set up ice chill plates on a large scale in temporary pop up bars in arenas. I use raw glycol plates like these:

This particular one is a 4 coil plate that had 2 products running through it, looped so the beer travels through two chilling circuits. It was one of 3 that between them dispensed close to 3000 litres of beer in a 7 hour period at a Melbourne race track. The only time we experienced foaming / warm beer issues was when the drain was accidentally blocked. As soon as we cleared the accumulated water, the beer was good again.

I also hire out jockey boxes / portable bars from time to time. The largest percentage of service calls I get from customers is when they have stopped the water from draining. (Fiddling with gas is the 2nd - but don't get me started on that!)

The only time I would advocate leaving water in an ice chilled situation is if there is an agitating device to keep the water moving, otherwise it will stratify.

 

[n87]

2

A 7 was s l8 l8 2rgi8cj,eggs

Friends don't let Friends' pockets drunk post

 

[n87]

Bit of Narco here, but since the strange bump above, I thought I would read the thread, and add my opinion. A few of the members here have asked me offline about this topic

I have had a couple of guys ask me about whether it is best to drain water or leave it in when using an ice chill plate. I have learnt a lot from the posts @MHB has made on various topics since joining this forum and completely respect his knowledge, but in this instance I must disagree with this post from a few years ago:



I often set up ice chill plates on a large scale in temporary pop up bars in arenas. I use raw glycol plates like these:

View attachment 109198

This particular one is a 4 coil plate that had 2 products running through it, looped so the beer travels through two chilling circuits. It was one of 3 that between them dispensed close to 3000 litres of beer in a 7 hour period at a Melbourne race track. The only time we experienced foaming / warm beer issues was when the drain was accidentally blocked. As soon as we cleared the accumulated water, the beer was good again.

I also hire out jockey boxes / portable bars from time to time. The largest percentage of service calls I get from customers is when they have stopped the water from draining. (Fiddling with gas is the 2nd - but don't get me started on that!)

The only time I would advocate leaving water in an ice chilled situation is if there is an agitating device to keep the water moving, otherwise it will stratify.

When used at that rate, your data seems to suggest that convection is not acting fast enough to keep up and the consistent heat absorption (ice melting) is required
I would argue, when used, say camping at a rate of 1 keg (19L) a night, and usually only a couple of pints at once; the convection would be enough to keep the cold plate cold enough. In the camping situation, you would also want to ice to last as long as possible, which not draining will assist.

If I had a cold plate, I would love to do some experiments on this to see at which flow rate you would need to drain for consistent temps

 

[Pnutapper]

It is my experience that convection does not work quickly enough in a domestic party situation either (20 - 50 litres in a day.)

This is why ice bank chillers have agitator motors fitted to them to keep the water bath at a constant temperature. Post mix chillers have their soda carbonators submerged in an ice bath with sometimes 2 agitators in the bath.

EDIT: If you wish to experiment, and have a decent thermometer, try measuring different levels in your esky perhaps?

This is a domestic ice bank beer chiller with agitator. (The grey / black thing in the middle of the beer coils.)

Stainless coils for beer, copper coils for refrigeration. Although it is difficult to see - the copper coils are coated in ice. (Easiest to see in top left corner.) The motor has a propellor at the end to agitate the water bath, and keep the temperature constant.