Therminator/QD: Dielectric concerns

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wbutler

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So I've been doing some revamping on the post-boil side of my rig, adding a therminator, pump, etc. I've been looking at putting quick-disconnects on the therminator, and the only QD's I can find for garden hoses are, naturally, made of brass. I'm concerned about attaching brass fittings to the SS attach points of my precious (and expensive) therminator.

If I might be excused for going all high-school chemistry for a minute, galvanic corrosion occurs when two dissimilar metals are in contact in an acidic environment. In most residential water heater installations, the plumber has to take care to keep the (probably copper) water supply line electrically insulated from the (probably stainless steel) fittings of the water heater itself. This is done with a fitting called a dielectric union, which uses a little plastic bit to keep the brass/copper side from touching the stainless side while still applying pressure and keeping things watertight.

So has anyone used brass fittings on their therminator? Any corrosion issues? Alternatively, does anyone know of QD garden hose fittings that are made out of stainless or plastic?
 

Tonedef131

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I have had brass fittings on the water side of my therminator for over 8 months now and there is no sign of corrosion.
 

Boerderij_Kabouter

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You will likely be fine for a LONG time with whatever you choose.

If you want SS QD's, morebeer.com is the cheapest and best IMHO for our application. They also have polysulphone QD's (plastic) if you prefer to go that route. Using one of those (SS or plastic) would be my suggestion, but anything will be fine.
 
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wbutler

wbutler

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OK, awesome. Thanks guys. Overthinking things as usual, it looks like.
 

tgioiosa

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Yep, I have brass fittings on my Therminator also, and haven't seen any problems.

The galvanic potential between Brass and Stainless steel is pretty low, and should be OK.

-Tony
 
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