It's been about 10 years since I visited PLBG.com - -

I am beginning to worry about my 36 year old State water heater . . . I mean, how much longer can it last??

My neighbor just lost his 10 yo tank-type of WHeater and, another neighbor had to replace his 10 yo tankless unit about a year ago.

So, my question(s);

1) What has been the experience with longevity of the tankless units? Are some models lasting better than others??

My son installed a 'Eternal' tankless unit about 5 years ago and he just loves it!
I would love it too if it hadn't cost him $5000 (San Antonio) to install. [Part of his very high costs involved removing the existing sediment-filled tanks out of the attic and installing the new tankless unit in the garage.] {Adding a water softener system cost more!}

2) How about the relatively newer tank-type very high efficiency condensing units such as A.O. Smith or 'Eternal'? Maybe there are others . . .

HTP Phoenix

I can vouch for the Phoenix LD. Stainless tank, cupronickel heat exchanger. Nicely engineered unit. Lower BTU/hr requirement than the consumer-market HE tank-type units I found from Rheem and AOSmith.

It can't quite provide constant hot water at the rate of flow used here to fill the jetted tub, but the recovery time is, to me, remarkably short. If there's one person showering and no other uses, the burner cycles on and off even in winter, when the supply water temp is somewhere in the 33-40 degree range.

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Links to the State of Wisconsin Plumbing Code:
[docs.legis.wisconsin.gov]
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I am not a plumber.
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What size Phoenix do you have?

I have the 50-gallon, PH76-50.

*******************************
Links to the State of Wisconsin Plumbing Code:
[docs.legis.wisconsin.gov]
*******************************
I am not a plumber.
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