Bronze March Pump?

[DrYeast]

So I got a used March 809-BR pump at a yard sale for $7, supposedly it works, but it was worth the risk and a little work. The only question I have is, with the bronze housing, is that still good for wort? I was thinking of using it for recirculating the mash and also maybe for a whirlpool chiller, so it would need to be good under hot and boiling conditions. It's good for water, but what about bronze and wort (acid pH)? If it's not, I can just buy the plastic housing and swap it out right? Bronze is not directly mentioned in How to Brew, and there's a lot of fittings that are for kettles and are made of bronze, but I'm no metalologist. Palmer, I'm looking at you.

[Kbar]

Well, bronze is an alloy of Copper and Tin. How do you feel with your beer being in contact with those elements? March is farily good with anwering email questions. Ask them if the bronze head is OK for food/potable-water applications. So far, my web surfing does not point to any issues, but I would ask March. Good find for $7.

[ajdelange]

Every gallon of beer I produce goes through March 809 HS pumps with bronze heads. Water is pumped from the HLT to the mash tun through one, vorlauf is recirculated with a second which then pumps the wort into the kettle and finally that same pump moves the boiled wort through the chiller into the fermenter. The second unit has had about 3000 gal of hot wort run through it without any detriment. Remember that brewing kettles used to be referred to a "coppers" because they were made of copper. Naturally some is dissolving but this actually benefits the yeast though note that unprotected copper is no longer permitted to come in direct contact with acidic foods in commercial operations. I'd be more worried about lead (which is often added to bronze to improve its machining qualities) but as these pumps are not marked with a caveat against use with food or water I assume that the alloy is lead free or very low lead.

The real advantage of the broze heads is that they are more temperature tolerant than the plastic ones. They are rated to 250 °F and 150 psig.

[BrewTa2]

I've never worried too much about the odd brass fitting. If you want to really make sure there won't be any lead leaching from bronze, you could treat it with Cupric Acetate. Make a solution of 18g/l and adjust the pH to 4 with vinegar. Circulate this through the pump for 20 minutes and any lead on the surface will be replaced with copper. Soak any brass fittings in the same solution.

Cupric Acetate available here.

[blipiddybrew]

I've never worried too much about the odd brass fitting. If you want to really make sure there won't be any lead leaching from bronze, you could treat it with Cupric Acetate. Make a solution of 18g/l and adjust the pH to 4 with vinegar. Circulate this through the pump for 20 minutes and any lead on the surface will be replaced with copper. Soak any brass fittings in the same solution.

Cupric Acetate available here.

wouldn't the two part vinegar to one part hydrogen peroxide soaking solution work, or is that for brass only?

[ajdelange]

No, not worried. The bronze is FDA approved low lead.

[DrYeast]

Thanks for the input everybody.

I wasn't worried about the copper, as my chiller hasn't killed me yet, and that gets a solid 20min boil every brew day. I was more concerned with the other metals in the bronze other than copper. Though I just listened to the metals Brew Strong, and apparently my brass fittings on my mash tun contain lead and I should have treated them, oops.

I might has well stick with the no worries plan, and keep the bronze head and put some time into getting the pump wired and plumbed into my system. $7 for a March pump is a sweet deal, and I'm stoked about it.

Thanks all.

[BrewTa2]

wouldn't the two part vinegar to one part hydrogen peroxide soaking solution work, or is that for brass only?

Oh yeah, that should work too. But, FDA approved is good enough for me.