Putting a UPS on a Rinnai Water Heater

How does that differ from a summer winter hookup? Do you have a well or city supply? If city, does your pressure maintain during power outages?.
We have wells so I love our Rinnai system . AT 6 gpm and centrally located so that we can "mine" the excess heat in the vent, we get quick hot water and we have enough to do several tasks that demand hot water, simultaneously. Summer winter hookups, besides just continually heating up a hot water reservoir whether yous use it or not, would always give up after a few minutes of hot water double demand.

Im sorry you dont like yours but did you locate it properly? or do you have a loooong run of hot water to your points of use?

Are you typing in code??...what has all that to do with the asking if I can put a rechargable battery on my water heater so that I can have hot water when the power goes out like I used to get with my hot water tank?

Why not a smaller battery and a piezo system.
Are you always this touchy about little things? Youve been kvetching about the tankless syetms that I have to laugh about why anyone talked you into one??

A piezo starter will shut off INSTANTLY. A battery and resistance circuit can keep igniting if theres a gas leak. I have a gas detector in the crawl space that has the two Rinnais.

UPS means uninterrupted power supply, which is like a battery, often used for computers. You know this right?

Ya, I got sold....I am not proud if it. What did it was that my old tank came close to rupture before I noticed and I have a lot of expensive stuff in the garage...I was thinking that I got rid of the danger of a flood and also would over the long haul save money. It was also a rush decision, as my tank was in very sad shape. What I did not know however was that due to energy savings not being as great as claimed water use going up because of the damn thing plus the cost of changing over from tank to tankless that there is almost no chance that I will ever get my investment paid back. It was the uneconomical choice, plus it vibrates my kid's wall and thus makes noise inside the house, plus waiting longer for hot water is a pain in the ass.

I pride myself on being smart and making good choices, this was an unusual bad choice from me so it sticks in my craw.

Why would it require you to wait longer for hot water? Did you replumb your house when you put it in?

The heater needs to kick on and get the water hot, it does not draw from a pool of hot water.. Also, my pipes are copper and it is a good run, the tank was set at 140 degs, the tankless is 125, so I am convinced that another few seconds more is wait time is due to the heat from the water being bled off into the pipe. The hotter first rush of water gets the pipes warmed up faster. Lastly, when I used to put my hand on the hot water outlet pipe on my tank it would be hot even if no hot water had been used lately, now of course the outlet pipe is stone cold, so yet more heat is bled from the first rush of hot water.

All in all getting hot water out of the sink the furthest from the water heater now takes more than 50% longer by my guess, it is was not a great situation to begin with.

thanks.....have not done it yet but I am sure I will regret it if I dont