[Yapakanichi]

Alright my peeps,

My water heater is about 11 years old. It was with the house when I purchased it. It works, but it takes a long time for the water to heat up and I would like something a bit more efficient.

What are the thoughts on switching to a tankless heater? It's just me and my wife. No plans on having kids in the future. So we just have the dishwasher, washing machine, and the shower. The shower heads share the same wall just the opposite side. We have ran out of warm water a few times while showering. Now granted our shower has 2 shower heads and there were 2 people in the shower at the time.

Another reason I'm beginning to think about this is because the shower on the opposite side of the house takes forever to get warm. Same with the kitchen sink if the dishwasher or washing machine had not just ran.

[kscarrol]

We've had a tankless for years love it, endless hot water! But there are some things to keep in mind about switching. Do your research on the cost to install versus your current water heater. We have a gas heater which is great. All tankless heaters have a minimum flow rate to trigger heating. Can't recall the exact numbers now but our old tankless required something like 0.5 or 0.7 gallons per minutes to turn on. Not an issue during the winter but during the summer when the "cold" water is already 80 degrees the heater would kick on and off because of the low flow shower head not demanding enough hot water. We switched to a newer heater with a lower flow rate of something like 0.25 gallon per minute and that has resolved the issue.

[zx10guy]

I just went through a replacement of my hot water heater. I got almost 19 years out of it. And it was still functioning, but I wanted to replace it before it leaked. 75 gallons of water leaking into a finished basement would be a very bad day.

So I looked into going tankless. Here are some considerations you need to look into before thinking about going this route. First, you have to see if the gas supply line you have will be able to keep up with the BTU load of the tankless heater. The new hot water heater I had put in is rated to 40,000 BTUs. A tankless is if I recall correctly around 200,000 BTUs. Next, you have to survey where you are going to install this tankless heater. The venting is not the same as your tanked heater. It requires a different venting system. Other practical issues which may or may not be a big deal for you. Tankless heaters work when there is water flow. So you will not get instantaneous hot water. Be aware of this. And you have to know how to flush the system to ensure proper service life.

With all of the above, I opted to stay with a tanked hot water heater. Got one from Lowes during one of their 10% off sales if you use your Lowes Credit Card. I went with a 50 gallon versus going with an exact replacement of my 75 gallon from the builder. I don't miss the lower capacity as the 50 gallon is pretty efficient. In fact, I have the temperature setting dialed down pretty low because the water comes out pretty hot for me. I also added a catch pan which wasn't code when my house was built. Now I don't have to freak out when the water heater starts to get to that age where the tank may fail. I have the catch pan piped directly to a floor drain that goes to my sump pump.

[rebekahb]

When we remodeled the house we bought we took out both hot water heater tanks and installed Rinnai tankless hot water heaters. We have liked them especially when we have friends come stay with us & you never run out of hot water. I also like that I don't have to worry about it leaking or failing one day. The negative for me is that my gas line is on the opposite side of the house from the kitchen so in the winter it takes a while for the water to get hot. My showers are never an issue but my master bath sink takes a little longer. All in all I would make the same decision again and ours are gas.

[omasou]

You want one of these...

https://www.navieninc.com/series/npe-a

[omasou]

Originally Posted by rebekahb

When we remodeled the house we bought we took out both hot water heater tanks and installed Rinnai tankless hot water heaters. We have liked them especially when we have friends come stay with us & you never run out of hot water. I also like that I don't have to worry about it leaking or failing one day. The negative for me is that my gas line is on the opposite side of the house from the kitchen so in the winter it takes a while for the water to get hot. My showers are never an issue but my master bath sink takes a little longer. All in all I would make the same decision again and ours are gas.

You can either do a traditional recirculation system (see the graphic in the Navien link above) or add an under the counter/smaller tankless water heater close to the shower to take out the initial chill.

https://www.bosch-thermotechnology.u...ers-1098966-c/

[omasou]

Originally Posted by zx10guy

I just went through a replacement of my hot water heater. I got almost 19 years out of it. And it was still functioning, but I wanted to replace it before it leaked. 75 gallons of water leaking into a finished basement would be a very bad day.

So I looked into going tankless. Here are some considerations you need to look into before thinking about going this route. First, you have to see if the gas supply line you have will be able to keep up with the BTU load of the tankless heater. The new hot water heater I had put in is rated to 40,000 BTUs. A tankless is if I recall correctly around 200,000 BTUs. Next, you have to survey where you are going to install this tankless heater. The venting is not the same as your tanked heater. It requires a different venting system. Other practical issues which may or may not be a big deal for you. Tankless heaters work when there is water flow. So you will not get instantaneous hot water. Be aware of this. And you have to know how to flush the system to ensure proper service life.

With all of the above, I opted to stay with a tanked hot water heater. Got one from Lowes during one of their 10% off sales if you use your Lowes Credit Card. I went with a 50 gallon versus going with an exact replacement of my 75 gallon from the builder. I don't miss the lower capacity as the 50 gallon is pretty efficient. In fact, I have the temperature setting dialed down pretty low because the water comes out pretty hot for me. I also added a catch pan which wasn't code when my house was built. Now I don't have to freak out when the water heater starts to get to that age where the tank may fail. I have the catch pan piped directly to a floor drain that goes to my sump pump.

BTUs need to be enough to heat the water as fast as it goes by. So if you have 1-2 showers, dishwasher and washing machine running can it provide hot water. The one I linked to can.

Condensing tankless use PVC venting. If you have a newer efficient heater then you have similar venting. The initial cold shock or adjustment cold shock is mostly from clearing the cold water from the pipes, which depends on distance of that outlet.

Builder had initially installed a Takagi--suppose to be a good brand--and that one had a horrible cold shock even once the pipes were cleared of cold water. The Navien uses different technology to eliminate that.

[Yapakanichi]

I have not read all the replies, but I'm noticing a trend, I do not have gas. I'm all electric.


Ok read replies. So the hotwater never goes away? That would be nice.

[kscarrol]

They are available in electric as well

[glockz]

For those who have made the switch to tankless. Is there any regular maintenance involved? I've read conflicting information on this or it could be based on the unit you have.

[kscarrol]

I have the company who installed ours do an annual maintenance as our water if fairly hard so we get scale though that would be true with a traditional tank water heater.

[Yapakanichi]

I should also mention I have a rainsoft water purification/softner system on the house as well. It's before the water heater. So it's directly city input water into my house --> cleaner --> heater

[vreihen16]

Waiting for hot water at a distance issues aside, you may want to look at heat pump electric water heaters. Our power company is offering a $750 rebate, and the feds have a $300 tax credit. Given the prices for a qualifying unit at one of the nearby big-box stores here, you could do the upgrade for only $120.....

[Clark_Kent]

Originally Posted by omasou

You want one of these...

https://www.navieninc.com/series/npe-a

+1. Had a home built at the end of 2018 with an NPE-240A installed and it's a fine unit. It's incredibly efficient and the performance has been excellent. I have zero complaints.

[Ngilbe36]

Wow. Crazy timing on this. Mine has been acting up and now refuses to light back up. I am caught between trying to fix it and just getting a new one. I believe I know what is wrong with mine and can fix it for $140 in parts. The issue is, its 12 years old and probably close to on its way out permanently. So with that in mind ive been researching new. I have decided on going to tankless for efficiency sake. I have a small house and I am not worried about needing too much hot water. 4-5gpm should be more than enough.

I have found that on a 1k tankless heater I can get about $400 in rebates between my gas company (they would do the same if I was electric) and the federal government. Something to look into or at least consider!

Good luck

[jwzimm]

On the Electric topic, you need to talk to a company to see if that is even close to possible. An electric tankless water heater would require much more than any other electric appliance in your house. We are talking on the order of 100+amps just for the water heater. Considering that most house electric services are 100-150amps from the street you would need to upgrade your service from the power company to even have a chance of making it work. Plus there is the cost of a new breaker box and the heavy gauge wiring needed to supply that sort of draw. Then there are the issues around uneven power demand. Power companies need to balance their grids and adding on such a high demand device that is not consistent causes all kinds of havoc for them. Some power companies have even switched over their billing practices to base charges on peak demand rather than total kWhr usage each month.

Bottom line, unless you have an existing gas water heater, tankless is not likely in your future.

[Dog Face Pony Soldier]

Originally Posted by jwzimm

On the Electric topic, you need to talk to a company to see if that is even close to possible. An electric tankless water heater would require much more than any other electric appliance in your house. We are talking on the order of 100+amps just for the water heater. Considering that most house electric services are 100-150amps from the street you would need to upgrade your service from the power company to even have a chance of making it work. Plus there is the cost of a new breaker box and the heavy gauge wiring needed to supply that sort of draw. Then there are the issues around uneven power demand. Power companies need to balance their grids and adding on such a high demand device that is not consistent causes all kinds of havoc for them. Some power companies have even switched over their billing practices to base charges on peak demand rather than total kWhr usage each month.

Bottom line, unless you have an existing gas water heater, tankless is not likely in your future.

As an all-electric condo dweller I've looked into this and the situation is not as dire as your predictions. What I think you're missing is the home already has an electric water heater. There are tankless options that draw no additional power. Actually over the course of a day/week/month you're using less electricity. The only question is are the tankless systems capable of keeping up with how the residents are using their home. My conclusion for me and my home is "absolutely."

This is the unit I'm moving to... Rheem 240V Heating Chamber RTEX-13 Residential Tankless Water Heater https://www.amazon.com/dp/B01NAUZJPE..._kTWMEbHFQ7CHH

The other benefit for my 750ft^2 condo is the tankless system is much smaller. I can reclaim much of the space the tank was taking up.

[F32Fleet]

Originally Posted by Yapakanichi

I have not read all the replies, but I'm noticing a trend, I do not have gas. I'm all electric.


Ok read replies. So the hotwater never goes away? That would be nice.

Heat pump water heater?

[bayarea328xit]

Originally Posted by F32Fleet

Heat pump water heater?

Had GE GeoSpring heatpump for 7+ years - when the tank leaked, they replaced it with Bradford White AeroTherm under warranty - link.

We have a recirc loop for the hot water throughout the house.

[RickFLM4]

I’ve looked into this when we remodeled our master bath (also no gas service). I had a thread about it a couple of years ago. The master bath is in the opposite end of the house as the electric panel so it would have cost more for the electric work than to bury a propane tank in the front yard and go with a gas tankless. Either way it was a lot of money. We opted for a new tank.

[nyalpine90]

Ao smith, Bosch are good elec hot water heater.
Make sure you have mixing valve and hot water return line.

[advrider6510]

According to the U.S. Dept. of Energy, a tankless water heater is more efficient and uses less energy than a conventional water heater, providing a $25 to $107 in annual savings.
It is quick too !
If your hot water use is low (less than 41 gallons per day), a tankless water heater will be 24% to 34% more efficient.. hope this helps