Install this:
The best among the brass ones.
Be sure to remove when your heater dies and reinstall on new one. No new WH valve can compare.
That plus a new anode rod will extend the life and performance.
The OP's may be too old for this however.

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The best among the brass ones.
Be sure to remove when your heater dies and reinstall on new one. No new WH valve can compare.
That plus a new anode rod will extend the life and performance.
The OP's may be too old for this however.