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Glycol -Seals and o-ring deterioration

Hans19 Member Posts: 1
Hydronic System -gas boilers (500,000 Btu)-base board registers.

Are their reports of any of the major brands of anti-freeze causing deterioration problems with circulating pump seals, o-rings in propress fittings and or system gaskets?


  • Snapdaddy
    Snapdaddy Member Posts: 2
    Pump seals....

    We haven't had issues with o-rings / gaskets, but have found that Ethylene Glycol (Dowtherm) doesn't get along well with the zinc plating in circulators.  More specifically, B&G PL circs, where the seal fits into a recess in a plate, we get corrosion and a leak.  Hope this helps...
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