Left Shirron plate chiller in Star San, formed crystals/deposits

[MBasile]

Anyone have any clue what those deposits are, and whether or not a FUBAR'd my plate chiller? Should I boil it, bake it, or bin it?

 

[friarsmith]

Probably calcium/mineral deposits. Remove any rubber/plastic/silicone fittings and bake it for 1-2 hours at 450. Then turn off your oven and let it cool slowly. Then flush with hot pbw water and some sanitizer and drain completely.

Same thing happened to me a few months ago. Bake, rinse, re-sanitize. It's all good now.

 

[friarsmith]

You could also try soaking it in some CLR, then flushing it. If that doesn't work, the baking approach should...

 

[MBasile]

Thanks friarsmith!

 

[MBasile]

Unfortunately Friarsmith's baking and cleaning didn't work, it still looks, well, not great. I baked it at 450˚ for 2 hours and then (once cooled) soaked it in Oxiclean (not PBW).

Any thoughts?

 

[friarsmith]

Yeah, that's still pretty grody. It doesn't look like a percarb/bicarb cleaner is enough.

You probably need to go the acid route. Check out the link below

https://groups.google.com/forum/#!topic/alt.home.repair/JnsWDyyUbX4

In order of strength (low to high), perhaps try:

CLR, acidic cleaner like Lemi-Shine, or pool grade muriatic acid. I helped my father-in-law clean several metal parts of a pool pump and filter last summer which was crusty with mineral deposits. We used a diluted solution of MA to soak parts and it worked great. Just be sure to read the instructions and dilution ratio. Available at most big box hardware stores for under $10. Also has lots of other household cleaning uses.

 

[SleepyCreekBrews]

That may be some kind of copper phosphate crystal formation from the phosphoric acid reacting with the copper that the plate chiller is brazed together with. If that was mine (and I have one myself) , I'd do some serious chemical research on what that is and how to clean/dissolve it, before I tossed it in anything else .

I know for a fact that Phosphoric acid (that's what starsan is) reacts with iron to form iron phosphate , so I would't be surprised if it does something similar with copper.

FWIW, Iron phosphate is quite inert , it's typically used to form a primer-type coating on steel before painting, but I have no idea about copper phosphate .

 

[MBasile]

Thanks friarsmith and Steve.

From my research, copper phosphate appears to be blue and easily disolves in water (I think). So that is possibly low down on the list of issue.

After my heated oxiclean bath I let the pot get to boiling (I was desperate) so now there is some rust forming. I'm going to try CLR tomorrow, but do I then have to "repassivate" the metal?

 

[MBasile]

SUCCESS! The purple bottled ZEP Calcium, Lime and Rust Remover did the trick! I also got some powdered BKF to "repassivate" the exterior and flush through the inside of the chiller.

 

[Spauldib]

I have the same issue with plate chiller. Which CLR did you use? I only found more of a blue bottle Zep CLR such as this: http://www.homedepot.com/p/ZEP-32-oz-Calcium-Lime-and-Rust-Stain-Remover-ZUCAL32/100007333

It mentions not to use it on aluminum/copper/brass however. Thanks