Passivation - fill the entire kettle?

[MikeCo]

That’s a good question. I wouldn’t think the acid would harm the rubber, but I’m not sure. The adhesive that holds the rubber to the stainless could be a concern too. You could try wrapping that with tape to seal the acid solution out.

 

[pretzelb]

That’s a good question. I wouldn’t think the acid would harm the rubber, but I’m not sure. The adhesive that holds the rubber to the stainless could be a concern too. You could try wrapping that with tape to seal the acid solution out.

I was thinking I could use one of my old SS brewing pots but they have spigots on them and won't fit. I will have to see if I can get creative.

 

[Piggles22]

Any thoughts on recirculating citric acid through a stainless steel plate chiller?

 

[Bobby_M]

I wouldnt because it will dissolve the copper brazing and the plates are super thin. I use caustic on plate chillers because its usually clogged with organics.

 

[pretzelb]

That’s a good question. I wouldn’t think the acid would harm the rubber, but I’m not sure. The adhesive that holds the rubber to the stainless could be a concern too. You could try wrapping that with tape to seal the acid solution out.

It turns out it doesn't matter much for the near future because I'm an idiot and didn't realize my outlet is 4 prong and my new system is 3 prong. So I'm waiting on an electrician.

 

[day_trippr]

...or someone like him?

Set your Way Back Machine to 1968

Cheers!

 

[RPh_Guy]

That’s a good question. I wouldn’t think the acid would harm the rubber, but I’m not sure. The adhesive that holds the rubber to the stainless could be a concern too. You could try wrapping that with tape to seal the acid solution out.

Citric acid doesn't harm plastics or rubber parts.

 

[MikeCo]

Depending on your system, you may be able to buy or make an adapter to go from your 4-prong outlet to the 3-prong controller.

 

[IslandLizard]

It turns out it doesn't matter much for the near future because I'm an idiot and didn't realize my outlet is 4 prong and my new system is 3 prong. So I'm waiting on an electrician.

Depending on your system, you may be able to buy or make an adapter to go from your 4-prong outlet to the 3-prong controller.

Right!

The "4th prong" is connected to a dedicated neutral wire that's bonded to ground in your main (service) panel. It's modern day code; it prevents the (bare) ground wire from carrying any current. But basically, they do the same thing.
You may be able to just change the controller's plug to a 4-prong.

 

[Bilsch]

You only need a 4% solution according to NASA research so that’s 302grams acid per 2 gallons and not 454gm. That should save some money. As for a way to reduce your fill volume, don’t forget to put every other bit of stainless equipment that will fit in the pot and do it at the same time. Glass blocks would also be a good filler.

 

[ford2110]

Why would SS brewtech tell you to passivate with Starsan if it doesn't work???? You're not using the standard sanitizing ratio. . Their recommended ratio is a more acidic solution. I've passivated several vessels this way with no issues.

 

[Bilsch]

My bet is they got starsan mixed up with another 5Star product called Acid Cleaner #5 which will passivate because it contains nitric acid.

Unfortunately products containing phosphoric acid do not remove iron from the matrix. They just chemically aren’t capable of doing it so starsan absolutely will not work period, no way, not gonna happen, not even a little bit. Best you let that go from your head. It’s bad info.

 

[Bobby_M]

Why would SS brewtech tell you to passivate with Starsan if it doesn't work???? You're not using the standard sanitizing ratio. . Their recommended ratio is a more acidic solution. I've passivated several vessels this way with no issues.

I think the better path forward is to ask SSbrewtech to provide you with that answer. As them for a specific reference that says phosphoric acid will passivate.

 

[jimyoung]

So quick follow up. After reading lots here I determined that it's probably not needed to passivate my new SS Brewtech brew bucket, but also that it couldn't hurt. So I went for it.

I saved a bit of money by filling old milk jugs and pop bottles with water, but leaving a little air, so that they floated. This reduced how much acid solution I needed. Thanks for the tip! (NOTE: using an old cork to close a 2L pop bottle, filled with cold water.. then apply heat to 80c.. wasn't very smart. POP boom! almost hit my head!!).

After deep cleaning my old kettle and new fermenter with TSP and a soft cloth, I heated some water to 80c, added my citric acid to make a 4% solution, and did a 2 hour soak. Then put it back in the kettle, re-heated, and soaked again. Let them dry, and placed in the open air for a full day to let the oxygen get at it. Also, while doing dishes I noticed a rust spot on an old stainless kitchen bowl, so I scrubbed it well, and tossed it in to.. just in case it helps

I can't honestly say I see any visual difference. But on close inspection of the new fermenter, I see some machining chuff marks (very light). Also, some small pitting around where the external handles were welded on... some how it impacted the inside of the fermenter. So, I felt better about having done the passivation process, as at the least, it may add an oxide later to give some protection.

FWIW, my water did turn a /little/ yellow/orange. Not as much as I saw in pictures, but it was there. So it perhaps took out some iron for me.

 

[Bilsch]

FWIW, my water did turn a /little/ yellow/orange. Not as much as I saw in pictures, but it was there. So it perhaps took out some iron for me.

Nice, you made some ferric citrate.

 

[Gruel]

Nice progress! You really don't know what they (the manufacturer) used to work on the surface. Maybe they gave it a good scrubbing with steel wool. That would certainly leave iron behind.

Regarding phosphoric acid: I think some rust converters contain it. You can also phosphatize steel as an anti-corrosion base layer for another coating. I don't think it would work on stainless though.