water heater failed .. need a new one ... tankless?

[albireo13]

We have a 40G capacity tanked water heater which has sprung a leak and needs replacing. We moved into the house 2.5yrs ago so, not sure on the age.

Anyway, I am thinking of replacing it with a tankless system but, have no experience with them. The concept sounds great but, I don't want to run out of hot water in a shower!

We have natural gas and a 2-shower home. Two adults but, possibly more if guests stay over or one of the kids has to move home. : )

Looking for feedback from users of tankless water heaters. Are you happy with them? Any recommendations?

Thx

 

[finnski1]

We have a 40G capacity tanked water heater which has sprung a leak and needs replacing. We moved into the house 2.5yrs ago so, not sure on the age.

Anyway, I am thinking of replacing it with a tankless system but, have no experience with them. The concept sounds great but, I don't want to run out of hot water in a shower!

We have natural gas and a 2-shower home. Two adults but, possibly more if guests stay over or one of the kids has to move home. : )

Looking for feedback from users of tankless water heaters. Are you happy with them? Any recommendations?

Thx

When I built our house 23 years ago we had a tankless system that was supposed to give us all the hot water we wanted. It kept up with showers ok though not great, but my wife could never get a bathtub filled to the level she likes with hot enough water.
We went to an indirect 40g tank fired off of the boiler as another zone. It has worked great for the last 20 years. I wouldn't go back. To be fair I don't know if the systems have improved since then but I don't need to find out.

 

[albireo13]

When I built our house 23 years ago we had a tankless system that was supposed to give us all the hot water we wanted. It kept up with showers ok though not great, but my wife could never get a bathtub filled to the level she likes with hot enough water.
We went to an indirect 40g tank fired off of the boiler as another zone. It has worked great for the last 20 years. I wouldn't go back. To be fair I don't know if the systems have improved since then but I don't need to find out.

Yeah, that's the kind of thing I want to avoid. Maybe they've gotten better over the years?

 

[pb4uski]

We have a Takagi propane fired tankless system in our home in Vermont. In fact, not only do we use it for domestic hot water, but we also use it for heating... it heats the hot water that is pumped through our radiant slab on the ground floor and through hot water baseboard on the upper floor. We have no boiler or furnace... just the on-demand hot water heater a little bigger than a 30-pack sitting on the wall.

Our system has no problem keeping up and providing hot water for the shower. If domestic hot water is called for that gets a priority over hot water for heating.

We have a spa jetted tub downstairs and the on-demand hot water heater is used for hot water for that as well (once the jetted tub is filled with hot water as it pumps it is also heated by electricity to maintain a certain temperature).

Now if we were calling for hot water for the shower, spa tub, laundry washer, dishwasher and sinks all at the same time could it keep up?... I don't know but we have never had that situation occur... at the same time we've never had a situation where we didn't have enough hot water.

The only complaint that I have with it is that for some of the domestic hot water fixtures that are farther away from the on-demand hot water heater it takes a bit of time for the hot water to get from the hot water heater to the fixture, but conventional systems have that problem as well unless you put in a special hot water loop... and it's not enough of a problem that we have seen a need to do that.

But all-in-all, I am very bullish on on-demand, it has worked well for us.

 

[zinger1457]

I had looked into it a few years ago but decided against it, besides the extra cost for a tankless heater there was additional install cost. My gas supply line was undersized for a tankless and needed to be upgraded, a new vent system was also required. I use propane for my water heater, heating, and cooking, and it's hard to itemize how much is spent just to heat water but my guess is it's fairly low, under $100/year. I also replaced the new tank water heater myself so saved on the install cost, if I went with a tankless I would have had to hire someone to do it, total upfront cost for me was close to 5X more for the tankless.

 

[pb4uski]

One thing to think through... is your existing hot water heater natural gas or electric? I assume natural gas since you mentioned it. If it is natural gas, you'll need to check with an installer and see if a tankless can use your existing exhaust.

 

[audreyh1]

Our main complaint with tankless is how long it takes hot water to get to the destination. Other than that had been quite happy with it for 10 years.

Our Takagi developed some slightly erratic behavior a couple of years ago. We have to occasionally reset it outside. No product support locally anymore unfortunately. We need to replace it, but newer models don’t quite fit. Will have to figure it out.

 

[Dtail]

Funny you ask, as just replaced our system yesterday due to age plus our new home insurance wouldn't accept a 16 year old system despite no issues. I believe 50g and cost 1,425 installed. It is commercial grade, which is an upgrade from the Home Depot type generic ones.
We were told that the tankless would be in the 5k range and just wasn't worth it to us.
As an aside, it is also more efficient and the hot water is hotter and sooner delivered.

 

[calmloki]

More tempted by the hybrid water heaters.

 

[pb4uski]

I don't think that is a viable option for the OP... he lives in NH... it is currently 21F in Manchester and the overnight low is expected to be 7F.

 

[Out-to-Lunch]

Yes, they have improved.

I was an early adopter (~2005), and the Bosch unit I had was adequate. My biggest complaint of this older unit was "the cold water sandwich," which happened when you have hot water at a fixture, turn it off, then turn it on again (as with shaving or doing dishes). In the previous times, this would result in slugs of cold water in between the hot.

Last year, I replaced it with a Rheem 95 series. This operates like a dream. It turns on instantly, and has no cold-water sandwiches. It is hard to distinguish from a tanked heater, except that you would never run out of hot water. (I will say that I am confused by your fears of running out of hot water. That is one of the selling points of a tankless heater: you will NOT run out of hot water.) I was able to locate it closer to my hot-water runs than the old tanked heater, so I get hot water to the faucets more quickly than before.

 

[Aerides]

How old is your house? We considered tankless when getting our last heater, but were told the electrical setup would not work without quite an upgrade. Might want to call in a plumber to assess before you start shopping.

 

[Bamaman]

Since it's just the two of you and you've got the preferred natural gas hot water heater, you might consider putting another unit in like you have. I've stayed in many B&B's in Europe over the years with gas tankless heaters, and they made noise even when not in use.

But if you had a 40 gallon electric unit, I'd tell you to upgrade to a 50 gallon electric unit.

We've got two 50 gallon electric water heaters, and I had to replace one unit last year. We have 3 1/2 bathrooms, one of which has a huge spa tub.

Thankfully our electricity costs are middle of the road per k/wh. My wife had a close by plumber do the job--and it cost substantially more than Lowes' installer. But the job was done right.

 

[pb4uski]

Since it's just the two of you and you've got the preferred natural gas hot water heater, you might consider putting another unit in like you have. I've stayed in many B&B's in Europe over the years with gas tankless heaters, and they made noise even when not in use. ...

Ours does not make any noise when it is not is use.

 

[tulak]

I had a tankless installed in my old house and loved it. Luckily all the water runs were close by, so no real issues with waiting for hot water. I never had any issues with running out of hot water. I think that’s be odd, since it heats the water as used, assuming that it’s properly sized for your home. I also had no issues with noise, especially when not in use.

I’ll look into a tankless again when I need to replace the hot water heater in my new place.

 

[Jerry1]

One way to look at this is break even point. Let’s make up some numbers. Let’s say replacing the current WH is $1500. Let’s say a tankless is $4500. Typical life of a WH is about 10 years unless you have hard water or some other issue. So, are you going to be in the house 30 years? Is the cost savings in fuel going to lower that break even time frame significantly? Personally, I’m thinking about replacing my tank. It’s a gas WH that came with the house. It’s 12 years old. I don’t want to wait unit it goes bad given the supply issues and how busy the trades are. I’d like a tankless system, but I think my money is better spent by getting the best insulated tank that can be installed in the existing space. My best guess is that I will not be here longer than 20 years. One never knows, but our next check point is at ten years when the youngest grandchild graduates high school.

 

[audreyh1]

Ours does not make any noise when it is not is use.

Yes, ours is completely silent when not in use.

 

[Irishgirlyc58]

I did a preemptive strike and replaced my 18 year old gas water heater.
I originally thought I would get tankless but after discussing the pros and cons I decided to just replace with a new gas water heater. 50 gallon for 2 people.
And half the cost at $1,500 for replacement, installation and haul off of the old one.
I would discuss your specific needs with the plumber and see if tankless would meet your needs.
All households are different.

 

[tb001]

I started a similar thread last summer—it was quite helpful, so you may want to search on that for more information.

We ended up installing a tankless and have been quite happy. We had a recirculation pump in place, so haven’t had the issues others have with time to faucet. I’m not sure why that would be any different with a tank unit. We have pretty high output showers and have had no issues running three at once, along with the dishwasher etc, but I assume you would need to size the unit accordingly, so ymmv.

Our tankless replaced two 75 gal water heaters. When we replaced them, the installer said we would likely need two tankless units in parallel, but so far one has been more than fine. The extra space in the water closet is a nice bonus.

I have two minor gripes. One, which others had warned me about, is that it resets whenever the power goes out and you have no hot water without power. Adding to that, resetting the unit is a pita. It resets the unit to a much lower temp and doesn’t turn on the recirculation pump. Reprogramming the system is not at all intuitive, so it’s a process to reset. And the power seems to be out often enough that it’s irritating. I need to plug it into a battery backup, which would solve 90+% of the annoyance, but haven’t done so yet.

My second gripe, which I don’t recall being mentioned in my earlier thread, is that as bamaman said, it’s loud. We have ours in an outdoor closet backing up to the laundry room, so it’s a non issue for us, but if I were working in that space more frequently it would bug me. You can clearly hear it through the wall. The installers mounted it on 2x4s to act as noise dampeners, so it’s definitely an issue for people besides just me. You don’t hear it unless it’s on, but when it’s on it’s louder than I would have thought.

Overall, we would do it again in a heartbeat. More space, performance is great, lower gas costs (enough to notice), and hopefully longer life/less catastrophic failure.

 

[Retired Expat]

We replace our electric tanked hot water with a hybrid. Love the savings and how it dehumidifies the basement. Since we travel a lot it is great to be able to shut it down from an app on my phone. Looked at tankless but power issues or venting a gas unit all added too much to the cost to make it worthwhile

 

[JoeWras]

1) Depends on the location where the heater needs to go. Closer to showers and kitchen is better.

2) Some locations create more difficult or ugly installs. My tank is center basement. Tankless could go here (and open up some space!), but venting will be ugly and a bit in the way due to low ceiling. The reason is a conversion from high heat atmospheric venting to condensing venting. The alternative installation in my area is on the OUTSIDE of the house. This is possible in milder climates. Problem with that is it creates a very long run to the showers and kitchen.

3) Gotta be gas. You may need new piping to allow higher flow.

4) Hybrid heat pump heaters sound good, but have downsides. Cold basements and not-trivial sound emissions are two of them. I would strongly consider these if my house was electric-only. The benefits could outweigh the downsides. But if I have gas, it is off my list.

We've decided to stick with the 40g tank and we are happy. 2 adults, no problems running out. Using low flow shower heads also matters. I found when we converted to them 25 years ago or so, we never ran out of hot water. The tank heater literally could keep up with the demand.

 

[albireo13]

OP here ....
I am going back and forth on tankless vs. normal tank. I am waiting on a call back from our plumber to discuss options and costs. I am usually handy and do things myself but, messing with plumbing has never been my forte. : )

My comments about running out of hot water is based only on my experience with our tank systems. With teenagers and my wife in line first, I was always having tepid showers. I understand the tankless unit will not have that issue.

The water heater is in our basement, near the furnace. It is natural gas, vented outside. I plan to stick with gas since our electricity costs in our area tend to run high. It is located just under the master bedroom which is good for our shower. The kitchen however, is a long run across the basement for the plumbing. The kitchen sink always takes forever to get hot water. I am considering installing a point-of-use water heater just for the kitchen sink/dishwasher.

 

[albireo13]

The water heater is in a dead corner of the basement so, space for a large tank unit is not an issue. If we stick with tanks, I would want to go with a high quality 50G unit ... just for extra margin in hot water capacity.

I am 66yo now and realistically our horizon for staying in the house is 20 yrs. From some quick number scratches, it would take ~20yrs to break even on cost.
The other cost issue is from talking with some plumbers, they give me 10-12 yrs as expected life of a normal tank water heater. That means we'll likely be replacing it again down the road.

If a tankless heater lasts 20yrs or more, I'd compare the cost of one tankless vs. the cost of two tank heater installs!!

 

[ERD50]

I don't think that is a viable option for the OP... he lives in NH... it is currently 21F in Manchester and the overnight low is expected to be 7F.

If that post was in ref to hybrid water heaters, they don't use outside air for the heat transfer, it's all done inside (and cools the basement in the process, which may be good or bad depending). But as others have pointed out, hybrids really only make sense if you are electric only, otherwise NG is cheaper initial and probably ongoing.

... Overall, we would do it again in a heartbeat. More space, performance is great, lower gas costs (enough to notice), and hopefully longer life/less catastrophic failure.

I really question the "lower gas costs". Water heaters just don't use much gas to keep the tank warm. It's the initial heating from ground water level that takes the energy, and that's common to both.

Perhaps your old water heaters had a build up of minerals and became inefficient? In that case, replacing them with a new tank-style could have seen lower gas costs as well. Not so much a function of tank vs tank-less.

1) ... We've decided to stick with the 40g tank and we are happy. 2 adults, no problems running out. Using low flow shower heads also matters. I found when we converted to them 25 years ago or so, we never ran out of hot water. The tank heater literally could keep up with the demand.

We were on a 40 G tank for decades with 2 adults and 3 kids and never ran out of hot water (OK, once when the pilot blew out!). I didn't even keep the tank set super hot (130~135F?). We were on a well, with a somewhat limited supply, so we were a bit conservative, just in case. So we didn't take 2 showers at once, or fill the wash machine while showering to prevent running through the reserve in the well, but that's all.

Some mentioned delays getting hot water with the tankless? I don't see why that would be any different (maybe a few seconds for initial heating - not really noticeable?). Unless you were running the water too slow to 100% trigger the tankless?

-ERD50

 

[qwerty3656]

We looked at tankless when we replaced our water heater, but things are so spread out that we have a recirculating pump so you don't have to wait for hot water - tankless didn't seem to make sense.