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      04-03-2017, 09:37 AM   #23
UncleWede
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The source gas and venting requirements are why I still have 50 gallons of water on the side of my house. My current 3/4 gas line comes from the neighbor's yard, under the house, and over to the heater side. GasCo would have to run a whole new line from the street to get me to 1.5" The current vent would need to increase to something like a 4" hole in the roof, about double the current size. I just have a hard time with cutting holes in the roof.

But, in the likely event of earthquake, I have 50 gallons before I have to drink out of the toilet. . .
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      04-24-2017, 09:52 AM   #24
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Quote:
Originally Posted by kscarrol View Post
^ Don't disagree the above issues...

Water softener requirement is dependent on individual location and honestly this would also be a good investment for a standard tank heater if the water is that hard.

Gas is best by far so that could be a deal breaker.

The venting requirements are required for any gas water heater, not just the tankless.

Water heater location. Is the tankless heater located that much further away than the traditional tank heater? Very well could be but for us both would be located in the attic so waiting for hot water to get to the dishwasher is not an issue. We would wait for hot water with either system.
Was the tankless system designed into the house or added after the fact. I am looking at building a house and I plan to put in a tankless system, tired of replacing water heaters and done two so far and the next house is the retirement house.

My research found that it is a good idea to put in a recirculating systems for long runs for hot water, what it does it circulates back the cold water until it is up to temp then it opens a value and let the hot water flow, it does two thing, help save water, it also helps saving a little heating energy since it does not have to spend as much time heating up cold water.

I was going to retro my current house with a tankless system, had two teenagers who loved long showers, but after finding out all the venting requirements and other things need to make it work correct I did not bother.

Also higher end dishwasher have their own heater. My dishwasher take my normal 140F hot water and heats it to 185F.
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      04-24-2017, 10:36 AM   #25
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Quote:
Originally Posted by Maestro View Post
Was the tankless system designed into the house or added after the fact. I am looking at building a house and I plan to put in a tankless system, tired of replacing water heaters and done two so far and the next house is the retirement house.

My research found that it is a good idea to put in a recirculating systems for long runs for hot water, what it does it circulates back the cold water until it is up to temp then it opens a value and let the hot water flow, it does two thing, help save water, it also helps saving a little heating energy since it does not have to spend as much time heating up cold water.

I was going to retro my current house with a tankless system, had two teenagers who loved long showers, but after finding out all the venting requirements and other things need to make it work correct I did not bother.

Also higher end dishwasher have their own heater. My dishwasher take my normal 140F hot water and heats it to 185F.
House was a complete gut and remodel of a 120 year old home here in New Orleans. Tankless was installed at that time though as I mentioned in an earlier post we upgraded to a new tankless several years ago.

Yes, you can do the re-circulating but our house is only 2,600 sq ft so the distance the hot water has to travel is never that great. This is why we did not install the re-circulating option.

As for venting, the original tankless was installed before we purchased the house. When we upgraded we found the venting was not up to code so we did have to correct that but I did not find a major issue.

And yes, modern, high-end dishwashers can heat water though I am not well versed on how efficient they are relative to the tankless heater. Just out of habit I let the hot water run until it is hot at the kitchen sink before starting the dishwasher...
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      04-26-2017, 06:12 AM   #26
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Dishwashers use electric heating elements. Cost compared to central water heater will be "it depends" but my bet would be that you're spending more by letting the water run until it's hot than you would by letting the dishwasher handle it.
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      04-26-2017, 08:38 AM   #27
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^ I have no data to dispute this but it sounds like you're going on a hunch as well. I have to think my tankless gas heater is more efficient at heating water than an electric heating element in my dishwasher. The offset of course is running the hot water for 30 seconds before starting the dishwasher! Ultimately the dishwasher is connected to the hot water line and is going to demand hot water, activating the tankless anyway so I imagine any cost difference is quite small...
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      04-26-2017, 01:19 PM   #28
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I have 2 tankless water heaters at my house. One for the upstairs and one for downstairs.

I also added buttons to turn on the water heaters in advance in the kitchen, master bath, and guest rooms. You push the little button, wait one or two minutes and you have piping hot water. No need to wait.

The newer models are much better and more efficient then the models of even 5 years ago.

I would highly recommend it.
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      04-26-2017, 01:46 PM   #29
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Quote:
Originally Posted by fkim119 View Post
I have 2 tankless water heaters at my house. One for the upstairs and one for downstairs.

I also added buttons to turn on the water heaters in advance in the kitchen, master bath, and guest rooms. You push the little button, wait one or two minutes and you have piping hot water. No need to wait.

The newer models are much better and more efficient then the models of even 5 years ago.

I would highly recommend it.
This is very good to hear, as we are currently building a new home and the house is ultra 'green'. I was initially concerned (still will be until I live with this new system) with giving up my very capable 50g Gas unit we installed 3yrs ago. The original lasted @ 13yrs! I don't have a prob if I can get a decade out of appliances and the such.
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      04-26-2017, 02:02 PM   #30
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      04-26-2017, 02:51 PM   #31
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I was watching 'This old house' On PBS and they were talking about a hybrid system that has a 5 gallon tank on a Tankless Design. It sound like just what I need, not sure if it is ten times the cost as most items are from that show.

Steve
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      04-26-2017, 04:17 PM   #32
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My house have a navien tankless unit.

Good things as other have already said, endless hot water, no / low risk of leak, etc.

But for my particular unit sometimes it take a while to run the hot water for it to start heating up (in some extreme cases can take couple of minutes, but most of the time heat water would start coming out in less than 30s). Never quite figured out why there is such a big variance of heatup time. Had couple of plumber took a look they have no good explanation neither.

That brings to my biggest gripe about these heaters - they're complicated machines. Most of the plumber really don't know very deep about them. They can install them, but if something goes wrong with them, in my experience it's hard to find people knowledgeable enough to give good diagnosis on them...
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      04-26-2017, 09:49 PM   #33
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Quote:
Originally Posted by byroncheung View Post
My house have a navien tankless unit.

Good things as other have already said, endless hot water, no / low risk of leak, etc.

But for my particular unit sometimes it take a while to run the hot water for it to start heating up (in some extreme cases can take couple of minutes, but most of the time heat water would start coming out in less than 30s). Never quite figured out why there is such a big variance of heatup time. Had couple of plumber took a look they have no good explanation neither.

That brings to my biggest gripe about these heaters - they're complicated machines. Most of the plumber really don't know very deep about them. They can install them, but if something goes wrong with them, in my experience it's hard to find people knowledgeable enough to give good diagnosis on them...
This was my concern about getting a tankless heater. They have improved in the 10 years since I looked at them I'm sure, but the complexity and cost of repairs made me stick with a standard tank heater. Just a thermocouple to go wrong, gas valve eventually, will have hot water even during a power outage. I found a tank heater that had 2 inch foam insulation, the heat from the pilot light keeps the water warm enough until I use it. And if you change the anode rod, tank will last for LONG time. An AO Smith I installed in my in-laws house is 26 years old and counting. Never touched it except to replace anode rod.
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      04-26-2017, 10:38 PM   #34
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Quote:
Originally Posted by lakefront View Post
This was my concern about getting a tankless heater. They have improved in the 10 years since I looked at them I'm sure, but the complexity and cost of repairs made me stick with a standard tank heater. Just a thermocouple to go wrong, gas valve eventually, will have hot water even during a power outage
last time for whatever reason my heater was giving out hot water with fluctuating temperature. got a guy out to take a look, whose company is supposed to be a certified repairer for the heater, he didn't really have much clue and just called the manufacturer and they sort of diagnosed it over phone. suggested me to replace couple of parts which will cost me 1k-2k! and i wasn't even convinced that the part they suggested replacing was the source of the problem. i ended up researching the problem myself and found some suggestion of maybe cleaning the inlet filter will help and did it myself, problem seems to have went away...

i feel like if anything seriously goes wrong with these heater, it would probably be time to get a new one instead of trying to repair them...
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      04-27-2017, 08:39 AM   #35
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Quote:
Originally Posted by byroncheung View Post
last time for whatever reason my heater was giving out hot water with fluctuating temperature. got a guy out to take a look, whose company is supposed to be a certified repairer for the heater, he didn't really have much clue and just called the manufacturer and they sort of diagnosed it over phone. suggested me to replace couple of parts which will cost me 1k-2k! and i wasn't even convinced that the part they suggested replacing was the source of the problem. i ended up researching the problem myself and found some suggestion of maybe cleaning the inlet filter will help and did it myself, problem seems to have went away...

i feel like if anything seriously goes wrong with these heater, it would probably be time to get a new one instead of trying to repair them...
Guy I worked with (a plumber) bought a Takagi tankless heater and was so horrified by all the circuit boards, etc that he immediately bought another one just to have parts on hand. This was 12 years ago or so, but at the time was about $1200 apiece. Better be saving a LOT of money on gas at that point.
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      04-27-2017, 08:51 AM   #36
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Quote:
Originally Posted by byroncheung View Post
My house have a navien tankless unit.

Good things as other have already said, endless hot water, no / low risk of leak, etc.

But for my particular unit sometimes it take a while to run the hot water for it to start heating up (in some extreme cases can take couple of minutes, but most of the time heat water would start coming out in less than 30s). Never quite figured out why there is such a big variance of heatup time. Had couple of plumber took a look they have no good explanation neither.

That brings to my biggest gripe about these heaters - they're complicated machines. Most of the plumber really don't know very deep about them. They can install them, but if something goes wrong with them, in my experience it's hard to find people knowledgeable enough to give good diagnosis on them...
I know mine has a small tank that is suppose to help that and I can hear it run every time I request water. In the morning it takes a bit but I believe most of that is to clear the cold water out of the pipes. Unless you install a recirculating system or smaller electric tankless heaters under sinks that will always be the case. So I don't see any difference tank in that perspective.

Just knowing I have endless hot water overcomes any downsides for me.
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      04-27-2017, 08:52 AM   #37
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Quote:
Originally Posted by lakefront View Post
Guy I worked with (a plumber) bought a Takagi tankless heater and was so horrified by all the circuit boards, etc that he immediately bought another one just to have parts on hand. This was 12 years ago or so, but at the time was about $1200 apiece. Better be saving a LOT of money on gas at that point.
I had a Takagi that froze up and I replace w/the Naviens. It's like comparing Dell to Apple.
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      05-02-2017, 10:16 AM   #38
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Quote:
Originally Posted by byroncheung View Post
My house have a navien tankless unit.

Good things as other have already said, endless hot water, no / low risk of leak, etc.

But for my particular unit sometimes it take a while to run the hot water for it to start heating up (in some extreme cases can take couple of minutes, but most of the time heat water would start coming out in less than 30s). Never quite figured out why there is such a big variance of heatup time. Had couple of plumber took a look they have no good explanation neither.

That brings to my biggest gripe about these heaters - they're complicated machines. Most of the plumber really don't know very deep about them. They can install them, but if something goes wrong with them, in my experience it's hard to find people knowledgeable enough to give good diagnosis on them...
It could be the temperature of the water coming into your house, it could vary as much as 20 degrees depend the time of year and the water usage around your area at the time. most time the water coming into your house could be around 50, but could drop to 40 and as high as 60.
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      05-02-2017, 02:11 PM   #39
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Quote:
Originally Posted by byroncheung View Post
That brings to my biggest gripe about these heaters - they're complicated machines. Most of the plumber really don't know very deep about them. They can install them, but if something goes wrong with them, in my experience it's hard to find people knowledgeable enough to give good diagnosis on them...
Agree about most plumbers being clueless, disagree that they're all that complicated. They're *precise*, and have sensors and motorized valves and whatnot. But they aren't hard to figure out.

I had an out-of-the-box issue with mine, fixed it with help directly from the Bosch folks. We diagnosed it over the phone, they overnighted the part, two spring clips and a wire connector, bada-bing.

Plumber was thrilled to let me do it, he was out of his depth. On the other hand he did a first rate installation job and knew all the building code foo plus tricks learned from other installs. Just don't ask him to fix it.
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      05-02-2017, 09:01 PM   #40
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Make sure you flush your tankless yearly especially in areas with hard water. I'm learning the "hard" way, our system takes longer to heat due to "scaling". Wish I knew this 2 years ago!

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      05-02-2017, 09:19 PM   #41
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Quote:
Originally Posted by ShakyDog View Post
I was watching 'This old house' On PBS and they were talking about a hybrid system that has a 5 gallon tank on a Tankless Design. It sound like just what I need, not sure if it is ten times the cost as most items are from that show.

Steve
That's what most European houses have had for years.
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      05-05-2017, 04:40 PM   #42
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I also put a gas tankless in recently. It had a couple of issues with it and Westinghouse sent me the parts. Replaced a mixing valve, it wasn't the problem, sent me a whole new electronics board for it. Even when broken I was able to turn it off and then back on and it would work for a while. Now 4 months later I am happy with it.

I did half of the install, mounted it to the wall and ran the exhaust and inlet outside. Decent hassle but if it ever has to get replaced again it will be far simpler.

Takes a little longer to get hot water but it cuts down the flow some until it gets there. So when taking a shower I turn it on earlier than I used to and not seeing a big issue with it. I would do it again.
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      08-11-2017, 07:26 PM   #43
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So 4 months later...

This isn't happening. Major electrical work required to get an electric tankless heater. Alternatively we could go with a gas tankless heater if we bury a propane tank in the yard (above ground not allowed where I live). So, the end result is skipping the tub in the bathroom remodel because it would cost $10K - $15K for tub / heater / electric or gas. (There is a tub in another bathroom.) We are just gonna stick with a new tank for the shower and sinks and leave it at that. Unbelievable how much time it took to reach this conclusion.
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      08-11-2017, 07:52 PM   #44
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Sorry to hear it. Do they make one-room tankless units? Might change the economics...
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