Good-by plate, hello counter-flow chiller!

[snowman_fs]

I got tired of slow flow, questionable sanitation, low efficiency and plugs while pumping through my plate chiller. So I built a true counterflow tube in tube chiller. 25 feet of 1/2" seamless stainless tube coiled inside a 3/4" copper coil shell. The inner tube is big enough to flow hops, and break right through. I used a coil to try and save space although it's about 26" in diameter. I also plan on keeping it downward sloped to fully drain when finished.

I used stainless inside for chemical resistance, the heat transfer difference between it and copper for a thin wall is almost irrelevant. Although the copper outer shell is so I can use the chilling water outflow in my next brew if I choose to (didn't want boiling garden hose water).



I'll post back when I have some run details. I'll boil a 40L pot of water and see how it chills in a single pass at full flow. I need to run a cleaning cycle through it anyway after fabrication.

 

[snowman_fs]

I guess I could also use this as a very fast acting HERMS coil. Almost like a RIMS but indirect by running the electric element inline with the outer shell. Since the volume is low compared to a typical HERMs the temperature could be stepped up rapidly with a PID and have no risk of scorching.

I would need to sort out the pressure increase in a closed heated loop but a small expansion tank or an open stand pipe could solve that. Or maybe just a PRV.

 

[Spyderbyte07]

I'm very interested in this, do you have a parts list? And estimated total cost? It looks like you cut the copper into several pieces and spliced it back together to get it around the coil?

 

[snowman_fs]

I'm very interested in this, do you have a parts list? And estimated total cost? It looks like you cut the copper into several pieces and spliced it back together to get it around the coil?

Yes I cut the copper into crescents while leaving the stainless un-cut. I tried to coil the two without sectioning but that proves to be more difficult than you might expect. I could get about 3/4 of a turn in before it would bind up.

Parts:
25 ft of 1/2" OD seamless stainless (coiled).
25 ft of 3/4" copper pipe (coiled and actually 7/8" OD).
5 x 3/4" Copper push connect tube-tube fittings (again actual OD 7/8").
2 x 3/4" NPT Tee
4 x 3/4" NPT bushing to 1/2" NPT (I try to use all 1/2" NPT in my brewery).
2x 3/4" NPT to 1/2" tube OD compression fitting.

Here is the tricky part. You need to ream the bore of the compression fitting to let the tube slide through. The fittings are designed to have a bottom stop as shown in the drawing. So I drilled it out with a 9/16" bit.



Total cost, not cheap. I had all of the "tools" needed plus many of the fittings already. I estimate it could be done for about $150 with online orders, free labor and in a shop with a good drill press and quality cutting tools.

 

[passedpawn]

Sharkbites? I love those things. Used them recently on some vertical 1" pipe that was full of water - sweating would have been a disaster. Those fittings work GREAT!

What temperature are they rated to? Maybe you should run the hot wort on the inner coil.

 

[snowman_fs]

Sharkbites? I love those things. Used them recently on some vertical 1" pipe that was full of water - sweating would have been a disaster. Those fittings work GREAT!

What temperature are they rated to? Maybe you should run the hot wort on the inner coil.

Yes, my plan is to run the inner stainless as the wort passage. The outer copper is to contain the working thermal transfer fluid (water).

SharkBite as a brand is good for 200F and 200 psi and 25 year warranty. I used TecTite fittings which are 250F and 200 psi for 50 years.

 

[bajaedition]

you do realize that SS is anodic and copper is cathodic ?

 

[IslandLizard]

you do realize that SS is anodic and copper is cathodic ?

Well, something needs to power his pump.

 

[snowman_fs]

No. The anodic potential between copper and 304SS is 0.15; suitable for even harsh conditions.

 

[passedpawn]

you do realize that SS is anodic and copper is cathodic ?

you do realize the anodic potential between copper and 304SS is 0.15?

(just had to be a smartass, I need to run off and see what that all means now)