On demand water heater

[John T Smith]

We currently have a 50 gallon water heater run on natural gas... it works, but there have been a couple times that we've run out of hot water when doing successive showers... so we've decided to have a Rinnai installed like we had at our last house
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After going to the Rinnai site https://www.rinnai.us/residential/solution-selector and answering the questions we decided that the maximum number of 'fixtures' we will ever run at one time is 3 and most likely fewer, but we don't want cold water in the shower again (3 fixtures could be dishwasher and clothes washer and the shower... probably not all at the same time, but cold water in the middle of taking a shower is really bad)
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I am an Army veteran so I get a small discount at Home Depot... as soon as our plumber visits to be sure what we want to do is possible I will place an order... the Rinnai is listed as .98 efficiency so I think we'll even get a deduction on next year's taxes (when we had to replace our DEAD furnace last year we got an energy tax deduction due to the new furnace being much more efficient)

[Nancy OShea]

If your tankless unit is very close to your tap, it makes sense.  Otherwise, it doesn't.

Descaling is another issue.  Hard water is no friend to tankless water heaters.

Where we live, a separate ionizer unit is an essential add-on expense.

Good luck with your plumbing consult.  Keep us posted on what you find out.

[John T Smith]

Hmm... I'll mention that to our plumber... he did all new 'pex' (I think that is the name of the tubing) when we gutted our 1957 house 8+ years ago... he also put in a circular hot water line with a special pump on a timer to have 'almost' instant hot water at every faucet in the house... after 7 years I had to replace the pump https://www.amazon.com/gp/product/B07DM3B8HD

[John T Smith]

Update and change

Wife said we MUST keep using the hot water pump, which draws water from the 50 gallon heater and puts it back in the tank after circulating... and can't do that with a Rinnai (or any other on demand unit)

So, no on demand heater