Time for a new water heater. Can we talk good/bad brands? How about Reliance?

Hot water heater longevity relies on the water itself...
If you have hard water, it will shorten the life span of your heater.
You are suppose to drain it once a year to flush out any sediment but, most people don't.

JD

neil_w said:

Sometimes it's just a failed valve, cheap to replace. I just had mine replaced on my 10 year old AOSmith unit.

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True. I've changed many of them.

Mushtang said:

True, but it'd rather go ahead and replace the whole thing since the tank has never been flushed and I'm working on finishing my basement and I don't want to take a chance. The point is that if the choice is $1,000 for tankless or $375 for a tank, I can't imagine going tankless yet.

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Can't argue with that, either.

I'm surprised at the size people mention, and I'm surprised at all the love for tankless heaters. We've had lots of trouble with them up here, but maybe it's the cold ground water temperature, not to mention pipe or regulator sizing problems.

I worked as a plumber for five years before going back to school (I'm a teacher now) and in that time I probably installed well over 1000 water heaters. I installed exactly one tankless heater. The only experience I have using them has been in Mexico and Ecuador - I wasn't impressed. I'm sure modern units installed correctly are somewhat more efficient than a good hot water tank, but I would think you would be lucky to recoup the additional cost within the lifetime of the heater.

From what I understood, the cost of the various models of heater was largely dependent on the length of the warranty, rather than any actual differences in construction.

As stated earlier, the longevity of a heater (tank or tankless) is mostly based on water quality. With neutral water and low mineral content heaters will last decades. Aggressive water will eat up most heaters in a few years. If you do have really bad water, a plastic/composite tank might be the best bet.

I swapped out my 75 gallon for a tankless unit.
Bought a BOSCH unit.

Like it for the endless hot water - especially when filling the tub.
Note two things:
- flow is lower than just a tank, so filling that tub will take longer.
- changes in flow effect the temperature until the unit adjusts and catches up with the flow change. So if you have more than one person changing the demand for hot water, you'll both be disappointed in the temperature of the delivered water.

If you go tankless Rinnai is hard to beat. keep in mind they work on water flow. Some homes have issues with smaller fixtures not having enough flow through it to start the unit. Read the manual 1st. If you go with an electric, Bradford White runs the best deal. 2 things to remember: 1.you do have to drain some water off each year. 2.Some models have a sacrificial annode rod that has to be watched and replaced when spent..my :2: hope this helps.

Marc_G said:

One thing to consider about tankless units is the incoming water temperature in your region (think, winter, coldest case) versus the temperature rise the unit is capable of.

If you live in a cold climate an have upper 30s F or low 40s F incoming water, and the unit can at maximum heat 60 degrees above incoming temperature, you'll never get the water hot enough to enjoy it. Check the specs for the heater you are looking at... a lot can only do a 35 degree rise at maximum flow rate, or a 60 degree rise at the lowest flow rate... Electric units generally can't raise the temp as much as a gas unit, but it will vary by unit.

When in ~2012 I was looking at a new water heater (replacing one under warranty, interested in upgrading tankless), the plumber here (in Indianapolis) cautioned me that the current crop of heaters wasn't up to the cold water temperature in winter in this region, and that it would struggle to keep a hot shower hot. He felt in the not too distant future they would be able to do enough of a rise to make it worth it. That was 4 years ago, so perhaps things have improved.

When my Bradley White tank unit dies, I will strongly investigate a tankless unit. I've got a gas water heater now, and would go gas tankless.

Marc

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I've been tankless for about 6 years in sunny Connecticut. We've had some -4 days and my Takagi tankless has worked just fine, hot showers after snow-blowing, even with the other shower running as well as the dishwasher When I put mine in, only a transplant from CA would do it.- the CT plumbers said the same thing, it would never work. Well, now in the summer my gas company sends me bills only every other month....still don't get a$20 bill.....

Tankless is not really going to save you that much money. It's advantages are fitting in a more constricted location and providing continuous HW beyond what your regular 40gal HWH will provide once the first 40 gal is used up. Also a tankless requires a different flue than a regular gas heater, unless the tankless is mounted outside the house on a wall.

Natural gas in most places will be cheaper than electric. Unless you want to get fancy and really complicated your best bet is to find a gas unit with the thickest tank insulation R-value and modify it with a ball valve and either a beefier anode rod or an electric anode. Check out Waterheaterrescue.com. These guys have loads of free advice.


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FredA said:

I swapped out my 75 gallon for a tankless unit.
Bought a BOSCH unit.

Like it for the endless hot water - especially when filling the tub.
Note two things:
- flow is lower than just a tank, so filling that tub will take longer.
- changes in flow effect the temperature until the unit adjusts and catches up with the flow change. So if you have more than one person changing the demand for hot water, you'll both be disappointed in the temperature of the delivered water.

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So if someone asks for hot and someone else ask for lukewarm do you get a average mix???

Andrew_ASC said:

So if someone asks for hot and someone else ask for lukewarm do you get a average mix???

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No, not at all. The temperature that the user "asks for" is controlled by the valve/faucet at the point of use.

What he is saying is that if you are taking a shower and someone else starts using hot water from a different fixture, then the temperature will drop momentarily until the heater increases its burn to make up for the increased flow. If that person then shuts off the hot water the shower temperature will go up until the heater lowers its burn to account for the reduced flow.


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So if someone asks for hot and someone else ask for lukewarm do you get a average mix???

Think about this....how does it work with a "regular" tank of water?
Your local mixing valves control the temperature in all modes - limited, of course, but the temps of the two input streams.

Tankless units have an output temperature target setting - they adjust the power input [gas or electric] to heat the water just enough to hit that temp for the given flow. Big changes in the flow require some time to get the power re-adjusted and the temp re-stabilized.

Tanks have a target temp too. You get that ONLY right after it finished a heating cycle. You don't see these changes when using a tank, because the temperature of the water in the tank is constant regardless of flow....or should I say constantly declining. As you empty the tank, the temperature will eventually match the input water and your heater will run with little temp impact.

You WILL save money with a tankless. The unit ONLY provides energy to heat water when using water. There are no losses while sitting "waiting" for use.

Think your insulated tank is good - try this -- turn it off before you goto bed and shower in the morning with the water....see how good it is....

FredA said:

<snipped for brevity>...You WILL save money with a tankless. The unit ONLY provides energy to heat water when using water. There are no losses while sitting "waiting" for use....

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While you may save money, whether you save enough to pay for the difference in cost is very use dependent. I live in Texas and use natural gas. I have two hot water heaters and when I looked into replacing them with a tankless system the payback period was literally decades if ever, and that depended on natural gas prices rising considerably and the units never breaking down.

The cost of natural gas is so low right now and especially in Texas the average temperature of the supply water means it does not take a lot of energy to heat the water. I simply did not spend enough on natural gas to ever save enough to pay for the extra cost of the tankless heater and installation costs in my house even if I converted to one heater.

Here's an example of a real world study of tankless heaters used in Minnesota. Its from 2012 but it's well worth looking over:

https://www.greenbuildingadvisor.com/blogs/dept/musings/are-tankless-water-heaters-waste-money

I was all 'fired up' for a tankless heater until I realized the only one that would make any money on the deal was my plumber. They make a lot on installation so they are somewhat biased in their recommendations.

There is nothing wrong with buying a tankless heater for the benefits of an endless supply of hot water but whether it actually saves any money over the long run is very user dependent.


Tony

That's a pretty interesting study. I guess I got off cheap with installation as it was only $750, and the guy who did it made sure I could replace it with a couple of wrenches only. I guess I'm hooked now :>

would be curious for a update. One of my neighbors did the two tank thing at the same time i did the tankless. I spent a little less, but he went for the big name brand heaters.

I keep thinking that the Mythbuster's screwed the pooch on their water heater experiments. They should have attached a camera and some electronics to one to capture the flights they achieved with their exploding water heaters. Also, I'd love to see a distance shot that shows the entire flight of the heater from ground to apogee and back.

I think someone touched on this a while back, but remember that Reliance is a brand name and not a manufacturer. That said, Reliance is manufactured by A.O. Smith which is one of the big players in the industry and generally has pretty decent quality control.

Agree that in many instances, the payback might never happen or take too long.
But - when faced, like myself, with a dead water heater and needing to buy a replacement, I went tankless for many reasons.

The primary reason is we have a big tub - 75 gallons (net, about 60 delivered) of hot water was not enough. When we built our house, I spec'ed twin 50's and due to an shortage at the time, got twin 75's. They were great - could fill the tub and more - but cost a pretty penny to keep both going.

When the first one died, I just disconnected it and we ran on one for a long time. But one was really marginal to fill the tub and recovery time was far beyond soaking time.

When the second unit died, I needed something and looked for a solution that fit our needs with the big tub. Another 75 gallon unit (with the required power vent) was nearly $1k. The same money bought me a 200k BTU Tankless.

I installed it myself - hardest part was REMOVING the old tanks.

Now - our summer gas bills are less than $10 where as before they averaged $35.

Given the net investment was about the same .... I'm thinking I'm saving money. YMMV

I went to a tankless heater for our cabin. Space was cramped and using a tankless heater really does save space, but the most important thing was that we might not go to the cabin for weeks (possibly months in wintertime) and when we’re not using hot water I didn’t want to be heating it. Every situation is slightly different.


Steve Shannon

Fred,

You definitely are an outlier in several respects. Very few folks have 75 gallon heaters and aren't faced with such a high replacement cost. You also use more hot water in one tub fill than the average family did in an entire day in the study I referenced.

More importantly the OP said he can buy a replacement unit for $350 compared to about $1,000 for a tankless system. So in his case he's a long way off before he sees any return. My point is your emphasis in your original post that tankless will save money is not true for everyone, and very likely not true for the majority of folks who go tankless.

Steve's example is a great case where even if the hot water heater doesn't save any money, it fits the use case a lot better. In our cabin we just turned the water heater off when we left but of course that meant no hot water for quite a while when we came back. Tankless would have been great.


Tony

manixFan said:

Fred,

You definitely are an outlier in several respects. Very few folks have 75 gallon heaters and aren't faced with such a high replacement cost. You also use more hot water in one tub fill than the average family did in an entire day in the study I referenced.

More importantly the OP said he can buy a replacement unit for $350 compared to about $1,000 for a tankless system. So in his case he's a long way off before he sees any return. My point is your emphasis in your original post that tankless will save money is not true for everyone, and very likely not true for the majority of folks who go tankless.

Steve's example is a great case where even if the hot water heater doesn't save any money, it fits the use case a lot better. In our cabin we just turned the water heater off when we left but of course that meant no hot water for quite a while when we came back. Tankless would have been great.


Tony

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I've researched the tankless versus conventional water heater thing. In doing the math regarding point of cost savings, it's important to consider the anticipated timeframe living in that house. Most conventional water heaters (in my area with hard water) die on or about their warranty expiration date, typically 6 years for the cheaper heaters. So, let's say there's a +$650 extra cost for tankless installation, and the tankless saves $60/year in gas (just for instance). Tankless units may need some minor maintenance along the way but have a lifespan 2-3x that of a conventional tank. I know people with 20+ year old early-generation tankless heaters going strong.

So if on day 1 you spend an extra $650 for the tankless, by year 6 you've saved $360 in gas, so you're only "out" $290 at that point. And, compared with the likelihood you would have had to replace the tank heater yet again within the next year or so, it's a break-even.

Of course, the math needs to be varied depending on cost of heaters, gas costs/savings, intention to stay in the house long term, quality of the heater purchased, time value of money...

When my heater (5 years old) goes up in a year or three, it's tankless for me. It will cost around $2k here for a high end gas unit of suitable capacity. The 5 year old heater actually was paid for in 2007, but that 2007 heater died within warranty during year 5 of 6, and was replaced for free (after much strong-arming of the company that had originally put it in in 2007... they tried to welch!). So actually I'm a case of being 10 years into a 6 year warranty. That POC tank heater in 2007 cost me ~$1500 installed, when the old one died on a weekend.

I must be living right or have good water. My heaters are about 10 and 15 years old. If you go back and look at that study one thing that stood out was that (gas) tankless heaters use a lot more electricity than regular (gas) heaters which is often not factored in to the costs.

But hey, I don&#8217;t have a dog in this fight, just after investigation into tankless heaters in my case I didn&#8217;t feel like spending a bunch of money to save the next homeowner on his heating bill.

Now hail resistant shingles, I&#8217;m all in on those. Had a 2 1/2 year payback just in lower insurance premiums and since my deductible is 1% the value of my house, if I never have to re-roof my house due to hail I&#8217;m way ahead.


Tony

There are tankless electric heaters and tankless gas heaters. The gas ones use little electricity, and some even use the water flow to generate sufficient small currents as needed for temp measurement and so forth.

I actually went back to the original source for the above article.
It was even more interesting (from the center for energy and environment in Minneapolis)
Most of the tankless conversions required gas line upgrade, which I'm sure added lots of extra cost
Which probably explains why I spent considerably less for the conversion, as my gas pipe was fine.
The other issue is the date on the study. publishing in 2012 ment that at the time tankless was still an emerging technology.
I wonder what the numbers would look like today, where there is much lower cost of acquisition, newer houses with "proper" sized gas supply and more willingness to install (driving down costs, when I did mine only one plumber would do it). Cost per therm of gas has increased so savings per year would also increase

They (CEE) did another presentation in 2014 where they looked at the experience of having tankless vs tanked. No great surprise that the assumed strengths were seen: tanked hot water heaters deliver hot water faster (67% response) but tankless completely dominated (85%) tanked for continuous delivery of hot water.....

Marc_G said:

Most conventional water heaters (in my area with hard water) die on or about their warranty expiration date, typically 6 years for the cheaper heaters.

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Be careful with your math here. If the water is sufficiently hard that it is shortening the life of standard tank type water heaters (which it shouldn't if they have adequate anode protection, but that's another story) then that same water will have a similar effect on continuous tankless heater. Instead of accumulating on the bottom (the hot end) of the tank the hard water scale will accumulate on the inside of the water lines where the heat is applied (electric or gas). From what I have heard, installers then recommend an annual flush of some kind (acid?) to purge the scale and preserve the heat exchanger. If you can't learn to do this yourself, the cost of an annual service call to do it will change the math regarding overall savings pretty quickly.

I do flush my Tankless every year.
SUPER SIMPLE.
upon installation, you install a flushing manifold at the water connections and yearly flushing is super easy.

Two wash-machine hoses, a small sump pump and a bucket is all you need.

Pull the plug and turn off the gas valve.
Take off the caps for the flush I/O.
Attach the hoses to the manifold and one to the pump outlet - the other dangles back in the bucket.
Twist the two valves.
Fill the bucket with 3 gallons of white vinegar from the store (about $5).
Let it run for an hour or two.
Stop - dump bucket - add fresh water and flush a bit before returning to service.

Easy-Peezy

I find it way better than flushing a tank - where the junk clogs the flush valve and you can never get it to seal again.
I had a plumber say the smart thing was to replace the drain valve at installation with a clog-free variety.
Thought this was wise.