Tankless/On Demand Hot Water System
- Cornelius_Gotchberg
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Tankless/On Demand Hot Water System
Considering an install, and seeking experiences, good or bad.
The Gotch
The Gotch
Madison WESconsin/Growing Zone 5-A/Raised beds above the Midvale Heights spade-caking clay in the 77 Square Miles surrounded by A Sea Of Reality
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Re: Tankless/On Demand Hot Water System
No experience , but check into federal and state energy efficiency rebates. You might actually get better for less cash upfront if an upgrade meets required specs.
-Lisa
-Lisa
- worth1
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Re: Tankless/On Demand Hot Water System
I don't have one but I've been around them.
One thing is they don't waste energy or water.
How many people do you know that turns on the hot water to wash hands or something but don't actually wait for the water to get hot?
One thing is they don't waste energy or water.
How many people do you know that turns on the hot water to wash hands or something but don't actually wait for the water to get hot?
Worth
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
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Re: Tankless/On Demand Hot Water System
They have to be flushed regularly. A gas fired one is better than an electric. I like Rheem Marathon tank style water heaters. Plastic tank never rusts out and they are the most efficient tank style available.
- Paulf
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Re: Tankless/On Demand Hot Water System
A couple years ago our old water heater needed to be replaced. We asked our heating and cooling plumber about the tankless system. He asked questions about our water usage, about our frequency of showers, washing machine usage, dishwasher usage and a few other questions I can’t recall right now. He looked to see how the system could be placed in our old house and whether we would or could use electric (that is how our regular hot water heater is powered) or propane, which would need a supply line installed.
The cost and usage analysis indicated for the life of each system a regular electric hot water heater would be the most cost efficient and reliable for us at the time of the analysis. Was it just easier to replace the old with a similar new? Maybe that was it; or maybe the study was valid. Technology is improving all the time.
It sounded like a tankless would be a good alternative but we got talked out of it. I suggest lots of research. Good luck and let us know how it works out.
The cost and usage analysis indicated for the life of each system a regular electric hot water heater would be the most cost efficient and reliable for us at the time of the analysis. Was it just easier to replace the old with a similar new? Maybe that was it; or maybe the study was valid. Technology is improving all the time.
It sounded like a tankless would be a good alternative but we got talked out of it. I suggest lots of research. Good luck and let us know how it works out.
- bower
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Re: Tankless/On Demand Hot Water System
The gas powered on demand hot water system was the norm in Europe when I lived in Spain. All gas appliances make me nervous so I wasn't thrilled but I have to say it worked. Never had a problem with it.
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm
temperate marine climate
yearly precip 61 inches/1550 mm
- worth1
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Re: Tankless/On Demand Hot Water System
There are so many safety features in gas water heaters it would make you head spin.
Much safer than a trip in a car.
Worth
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
- bower
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Re: Tankless/On Demand Hot Water System
I had a look at electric tankless heaters - they are more efficient than a tank, could save 14-34% depending on usage.
Couple of reasons not to go tankless: you won't get the same performance in some circumstances - reportedly not great for multiple demands at the same time. Also less optimal performance if the input water is really cold, and subject to accretion of minerals which reduce efficiency, if you have minerals in the water. Just for water temperature alone, I'm better off with a tank.
I bet you get great value and performance for it in a hot climate, where the water input is already not icy.
If the tankless weren't so expensive and complicated to install (vents required) multiple small units for task areas would work better for a busy household.
Couple of reasons not to go tankless: you won't get the same performance in some circumstances - reportedly not great for multiple demands at the same time. Also less optimal performance if the input water is really cold, and subject to accretion of minerals which reduce efficiency, if you have minerals in the water. Just for water temperature alone, I'm better off with a tank.
I bet you get great value and performance for it in a hot climate, where the water input is already not icy.
If the tankless weren't so expensive and complicated to install (vents required) multiple small units for task areas would work better for a busy household.
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm
temperate marine climate
yearly precip 61 inches/1550 mm
- PlainJane
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Re: Tankless/On Demand Hot Water System
I looked into them for my renovation and decided to go with a hybrid heat pump water heater. I won’t have feedback on it for a few months though.
“Never try to outstubborn a cat.”
- Robert A. Heinlein
- Robert A. Heinlein
- worth1
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Re: Tankless/On Demand Hot Water System
I can see a Simpsons episode with Homer replacing the water heater.
Worth
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
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Re: Tankless/On Demand Hot Water System
Hello,Cornelius_Gotchberg wrote: ↑Mon Jan 27, 2025 7:42 am Considering an install, and seeking experiences, good or bad.
The Gotch
I have installed a Navian Tankless Water Heater- It has Changed my life!!!!
Before , with my old 50 gallion high recovery water heater, i would get the ice water in the shower after 3 daughters and my wife would take care of some long locks. . '
Now, I can luxuriate with plenty of hot water. Best part, energy efficient- Not keeping 50-70 gallons of hot water all the time
Old Chef
- worth1
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Re: Tankless/On Demand Hot Water System
Speaking of staying in the shower too long, I had a brother in law that would use up all the hot water.
He also took a blow dryer to fish camp.
He would spend hours in the bathroom grooming.
He also took a blow dryer to fish camp.
He would spend hours in the bathroom grooming.
Worth
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
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Re: Tankless/On Demand Hot Water System
We have two Rinnai tankless propane water heaters on the property, one is ten years old, one seven years old. Both work great. Properly sized they provide more than enough hot water to do dishes, wash laundry, take a shower at the same time.
Not sure about really cold wx performance for obvious reasons. My heater is in my garage, so it does take about 30 seconds to get hot water in the house. The only repairs I’ve had to make are due to geckos climbing into moving parts and dying (thinking this shouldn’t be an issue for you).
Just know they’ve come a loooooong way since the shitty pilot light Palomas of the 1990s
Eta: No hot water when your power goes out unless you hook up a UPS and even that gives you just a bit of run time.
Not sure about really cold wx performance for obvious reasons. My heater is in my garage, so it does take about 30 seconds to get hot water in the house. The only repairs I’ve had to make are due to geckos climbing into moving parts and dying (thinking this shouldn’t be an issue for you).
Just know they’ve come a loooooong way since the shitty pilot light Palomas of the 1990s

Eta: No hot water when your power goes out unless you hook up a UPS and even that gives you just a bit of run time.
Wet and windy side of a Hawaiian island, just living the dream
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Re: Tankless/On Demand Hot Water System
We put 2 tankless on our new build due to our large household and the layout of our house. One supplies the kitchen, powder bath, and 3 outdoor showers. The other supplies the laundry room and 3 bathrooms. Can't speak to longeivity, as they are only 1.5 years old. But our household use is the equivalent of 3 to 4 average households. Performance is amazing. They are mounted outside, since we are in South FL, so we gained an interior closet that we would have used for a water heater. And it's the height of luxury to never run out of hot water, no matter how many people are showering and doing laundry.
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Re: Tankless/On Demand Hot Water System
I think I would start calling him my sister in law at that point
Wet and windy side of a Hawaiian island, just living the dream
- worth1
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Re: Tankless/On Demand Hot Water System
A little away from hot water but said brother in law also spent weekends with his friends and left my wife's sister at home.Mark_Thompson wrote: ↑Tue Jan 28, 2025 11:25 pmI think I would start calling him my sister in law at that point
I told my wife he was cheating on her.
She said I was crazy.
Then sister in law made the announcement but he said he wouldn't do it anymore.
Yeah right.
Well anyway he did they got divorced with a kid or two.
Haven't seen either one since 98 or so.
Has anyone heard of hot water circulation keeping the water hot at the faucet.
Worth
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
25 miles southeast of Waterloo Texas.
You can't argue with a closed mind.
You might as well be arguing with a cat.
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- Joined: Thu Dec 19, 2019 2:21 am
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Re: Tankless/On Demand Hot Water System
Yeah putting a timer on the heater and a return line so that the hot water could circulate and there would be instant hot is an option our plumber discussed with us. Decided not to as our water is almost free and our propane certainly isn’t.
Wet and windy side of a Hawaiian island, just living the dream