Your experience with natural gas tankless water heaters
 

Mrs. Pirate and I are 7 year residents of TV and plan to build and move to a new home in the deep south…that is south of CR-44. The default in new homes is a natural gas tankless water heater. We’ve never had one of them, so I’m hoping to learn from the experience of other Villagers who have natural gas tankless water heaters.

Overall, are you pleased with your natural gas tankless unit?…or if you had a do-over, would you choose a natural gas tank-type unit?

Do you perform the periodic flushes on the recommended schedule? How much time do you spend for each one?

If you don’t flush it yourself, do you pay someone to do it? How much money do you spend for each one?

If you’ve had a premature failure of your unit, it would be helpful to have input on the following.

What make/model unit do you have?
How long was the advertised warranty?
How long was it before you experienced premature failure?
How long were you without hot water before it was fixed?

Was your unit repaired under warranty at no expense to you? … OR …
Was your unit repaired at your expense because the warranty was void? What was the reason the warranty was voided? How much did it cost you?

Was your unit replaced under warranty at no expense to you? … OR …
Was your unit replaced at your expense because the warranty was void? What was the reason the warranty was voided? How much did it cost you?

I know this is a big ask, but I’ll bet there are others with the same or similar questions. Thanks in advance!

Rebel :)

Ours will be 3 years old next month and I have yet to flush it. We have a filter system as well as a softener system and don't have a problem with calcium buildup or clogged screens on our fixtures. It takes a while for hot water to get to the bathroom as it's on the other side of the house but it would take just as long if I had a tank heater. One great thing about having the tankless is you gain closet storage space in your garage where there would normally be a tank which is priceless.

We don't live in TV yet but have a Navien NPE-240.

This one is three years old and has never had a problem. The one we had before this was also a Navien but was a prototype. The only problem we ever had with that one was a defective motherboard which the factory immediately sent out a factory rep to diagnose and repair. Since that unit was one of the first of its kind in North America it got special attention. It lasted 7 years. I believe the current model has a 5 year warranty.

I would never go back to a tank type heater. I like the recirc function and I like never running out of hot water.

I do the periodic maintenance my self. Initial cost was a pump, Robot Check

A set of hoses. Robot Check

And a five gallon bucket. Now the only cost involved is the 2 gallons of vinegar I use to do the descaling and takes less than an hour. forty five minutes of that is pumping through the vinegar.

Might add - are the outside water pipes protected from freezing.
How do you want to use your hot water? Circulating pump running all day or at specific times so you have hot water at the tap or just run water until you get the hot water? Never had a thankless system but I think I would stick to the tank system. If you have a walkin tub then a larger (50 gallon) tax system might be better than 40 gal. Tankless might be best for the walkin tub but I have no experience in that.

I love our tankless on demand water heater. First, your not using energy trying to keep 40/50 gal of water hot 24/7. Second, you NEVER run out of hot water no matter how much you use.

Continuous hot water?
 

Has any owner of a tankless system ever - through normal use or as an experiment - challenged the advertising tag line that a tankless system provides continuous hot water? I was at a big box home improvement store last weekend and one of their experienced sales staff said that most tankless systems are rated to provide 56 gallons in the first hour...and then the water quickly goes from cool to cold.

I'm confused how that could happen if the water is being heated continuously as it is used. I understand how there's a lag between initial demand and actually having hot water at the tap - it's no different from a tank system - you either have a recirculation pump or you don't. But how can a continuously running gas powered heater have only a 56 gallon capacity for the first hour? Interestingly, the small print at the display in the big box store said something similar.

The sales agent also said peak demand (simultaneous use of clothes washer, dishwasher and shower) can overtax the tankless system and not produce sufficient hot water to produce a comfortable shower.

Again, I'm...nonplussed. Does anyone have experience with this issue...one way or the other?

Thanks again! Rebel :)

Smart
 

Very smart to do your Due Diligence.:bigbow:

We had a tankless system for our house in GA. The home was 4 baths, and a jacuzzi tub. I followed the maintenance procedure of de-liming the unit once a year. Used CLR. There were no problems and never had any problem hot water volume. I believe all the tankless systems have similar design features when it comes to providing hot water. That is: as the demand for hot water (volume) increases the system will provide full volume up to the point where so much water is flowing that it can not heat it to the desired temp. When that happens the unit begins to restrict the flow to maintain the outlet temp that it is set at.

The units I've seen in the new part of the Villages are on the small side and probably will begin to restrict flow if more than 2 spigots are opened. My recommendations - insulate as much as you can hot water pipes and regularly de-lime the unit (unless you have a water softener). Do NOT install a recirculating pump as that will void the warranty. It will also cause the tankless unit to run all the time which will significantly shorten the life of the system. There is a circulation pump (on Amazon) that can be installed at the furthest point to recirculate the water until warm water reaches it which will cause it to turn off. This will save wasting water but won't improve the time it takes to get hot water.

I don't understand how a salesman could tell you that the heater would stop heating water after a certain amount of time. It's basically a mini blast furnace. As long as it has a continuous gas supply and a continuous water supply it should run until you're tired of hot water. But to answer your question.. I have never run out of hot water. But then again I can't remember the last time I took an hour long shower either.

As far how many things you can run at a time.. That would be specific to each unit. Our unit has a 199,900 BTU/h capacity. Depending on how cold it is outside will determine the quantity of hot water it can produce. For example, the flow rate for a 35*F temp rise is 11.2 gallons per minute. A 45*F temp rise is 8.7gpm. A 67*F temp rise is only 5.6gpm. Our unit is mounted in an insulated garage so it never gets anywhere near freezing. And remember, that's just amount of hot water produced. Not the amount of water at the faucet once cold water is mixed in.

Our unit has a built in recirculation pump. But unless the house is plumbed with a return line or you can hook into your plumbing system to allow it to actually circulate it won't do you any good.

I have installed my own tankless heater (gas) in a different home.

In TV I have tankless and in a second home in TV a tanked electric heater.

On this forum I am known for my extensive home automation/monitoring and my DIY for, well, everything. And a distain for opinions not based upon actual facts.

Now to dispell common myths and inaccuracies.

You don't use much hot water, I know because I monitor both hot and total water consumption, separate from irrigation. Roughly 50% of your total or 25 to 45 gallons/day covers pretty much everyone of every living style.

No you DO NOT save a dramatic amount by not having to keep a tank of water hot. I know because the electric monitor checks electricity consumption 10,000 times per second. I completely under the standby costs of a water heat. The cost to heat the water from cold is where the money is at. Speaking of money an electric heater costs about 12.00 a month for most people. I know because I rent my home and I see different living styles as they relate to electricity consumption by people of varying backgrounds.

Tankless heaters are rated by flow. Two gpm is plenty and you will never run out of hot h2o. A tanked heater with a 50 gallon tank has 28 gallons of piping hot water, by comparison.

I flush mine annually for thirty minutes. Easy.

My opinion is indifference, I only want tankless because I get more space in the garage. I used to think the heater made a difference, now I can worry about more important things.

We live in TV south of 44, and we have a tankless hot water heater (all of the houses in our neighborhood have them). All of my houses prior to TV had tanked hot water heaters. Other than the space savings in the garage you gain with a tankless hot water heater, I prefer the tanked system. My experience is that you get hot water to the faucet faster with a tanked system. With a tankless system, the water has to be running for the system to activate, and then the heater takes time to fire up and start heating the water. In a tanked system, the water is already hot and ready to go. Both systems have to clear the cold water already in the lines before the hot water reaches the faucet (it is inaccurate to state that either system has instant hot water). You can install a circulation pump on a tanked system to help address this, but my understanding is there is not a comparable solution for a tankless system. And that is my biggest issue with a tankless system; we have found that it takes about twice as long to get hot water to the faucet compared to a tanked system (with no circulation pump). It takes almost two minutes for hot water to reach the faucets in our master bath (furthest away from the heater). So we are wasting more water with a tanked system, or just as often, wasting gas because I will turn on the hot water to wash my hands and finish before any hot water reaches the faucet. It is only my wife and I, and we have never ran out of hot water with a tanked hot water heater, so the endless supply of hot water with a tankless system isn’t a material benefit. We have spoken with several of our neighbors, and most have similar feedback with their tankless system as well.

I have no doubt that the water is instantaneously hot, but my biggest complaint is the amount of time it takes to push the cool/cold water through the lines before actually getting hot water at the tap or shower head. We had a 2 story house in Wisconsin with a 50 gallon water heater (NO recirculation pump) and always had hot water in about 10 seconds.

I built a home in 2005 and installed a tankless, gas, water heater. I spent $1100 as I recall and never had one problem with it in the 10+ years I owned the home. I never flushed it, but did check the filter. I was on a well and that may have made a difference. I am not sure that it saved me any $$$ over the years, but there was no water heater tanks to be concerned with either!

In the older high rise I lived in in Fort Lauderdale, many of us retrofitted the hot water system to electric tankless systems (no gas in the building). Some of us had a unit installed in each of the bathrooms in our apartments. There was no problem with how instant the hot water was. It came out hot and long lasting (i.e. we never ran out of hot water). The only problem any of us experienced was the quality of the water flow into the building. Fort Lauderdale water carries a lot of sediment. After the initial installations burned out a few units, there was a simple solution...additional filters added for the unit for those of us switching to electric tankless systems with minimal maintenance required. By the way, the under sink unit was no bigger than a BBQ tank and flat. It did not interfere with storage or aesthetics. The only downside was the initial cost for replumbing the bathrooms to a modest extent.

Keep in mind the units here in the villages do not have the recirculating feature that some people are talking about. I have done my own descaling after 18 months and it was not really needed. The person before explained the proChess accurately. Like the unit and extra storage space in the garage.

Other than the first few years here in TV where we had a tank heater ee’ve had nothing but tankless heaters for almost twenty years in three different homes. They operated very efficiently and without maintenance incident. I wouldn’t have anything else!

A couple of key points:

- They are more expensive to install initially, most having to do with the plumbing changes required for hook up. But once installed, the savings in operating costs quickly begin to repay that expense. You’ll see an immediate decline in your gas bill.

- Be sure you choose a model with enough capacity for your needs. The models we chose, while more expensive, could provide enough continuous hot water to serve two showers, the wash machine and dishwasher simultaneously! The tankless heaters are rated at how quickly they heat water from ambient temperature to your desired hot water temperature. Ambient water temp here in FL is a LOT warmer than in Michigan and Illinois where we were more than satisfied with the tankless units we had installed there.

- Hot water is provided at the heater almost instantaneously. However, like the tanked heater if you have long water lines from the heater to your faucet or shower, they have to be ‘filled’ with hot water before it is provided at the faucet itself. There should be no change between tanked or tankless if they are installed at the same location.

- Do your research, shop for sales. We had a Rannai installed here in TV by Allan Curry Plumbing. They also ‘descaled’ the unit about every 3-4 years. But if you want greater long-term confidence in a dealer, tankless heaters are sold and installed by both Lowes and Home Depot as well as most big box appliance dealers.

Just built in Southern Oaks, the water heaters are placed at the front corner of the garage.

It takes 2-3 minutes to get hot water to the shower. Temperature drop is more than 10 degrees over that distance

If I had a do over, I'd ask if possible to place it closer to the center of the house.

Otherwise I'd talk to a plumber about installing a small water heater near the master bath sized to cover the time to get hot water from the main unit.

Ohiobuckeye
 

You’re right it wouldn’t make any difference if you had a tank or tankless water heater it would take just as long to get hot water to the other side of the house. The builders could put a tankless water heater more to the center of the house if they really wanted to, because tankless are put in the wall but the builders I think don’t want to change anything. You would think since Florida is always saying the state is short on fresh water & TV waste a lot of water just running it so long to get hot water. Also tankless are cheaper to buy than a tank heater. Really I don’t see any difference which one you get unless when it’s time to get a new one, that’s where you can get a better deal on a tankless!

Outside water pipes are not ever going to freeze in the villages

:) A little off subject and does nothing to answer the OP's questions...... but important to someone reading this thread and thinking about converting to gas tankless from tank water heating. TECO has a great rebate program:

Conservation Rebates - Peoples Gas


Over the last several years we have received $1000 total in 3 checks.

1. $100 new gas stove (I installed)
2. $400 new High Efficiency Tank Water Heating (I installed)
3. $500 new gas furnace as part of new HVAC System (Chuck Farrell installed and filled out paper work - I got the check)

:coolsmiley:

"Efficiency" Related to Tank vs Tankless
 

Thanks to everyone who has provided feedback on my original question. I’ve read and re-read the entire thread and continued to do research online and at stores. Here’s where I am…at the moment…but could change my mind…again.

“Efficiency” comes up frequently when considering tank vs tankless water heaters and could be based on which is most convenience-efficient, cost-efficient, energy-efficient, or water-efficient. Each of these types of efficiency are impacted by (obviously) the specific water heater systems and whether we’re talking about (1) building a new home with the water heater location optimized for the house, (2) building a new home where the water heater location is determined by factors other than optimizing the system, or (3) whether we’re retrofitting an existing home.

In my case — and for most new homes — we’re talking about villages in the new sections of TV that are south and west of the turnpike: either (a) builder-spec homes or (b) homes customized by/for the prospective owner on a specific lot. Some Villagers may (c) retrofit their older home and convert from tank to tankless…but that’s a different situation and outside the scope of my consideration.

This has been an interesting discussion and research project. Depending on the specific application (location of tankless unit on house), the specific systems, and the time-frame for comparison (owning for 5 years vs owning for 20 years) one might conclude either is most “efficient” depending on the type of “efficiency” they find to be most compelling.

Most of us are (at least I am) more concerned with convenience/cost-efficiency than energy/water efficiency. And the most important cost consideration of all may be maximizing appeal to prospective buyers when (eventually) re-selling one’s home. In that regard I probably don’t want to stand out and be the only tank system in an area where every other home has a tankless heater, even if I have a personal preference for tank compared to tankless.

So, as of right now, I’m planning to choose one of the standard new home (tankless) options.

Thanks, again! Rebel :)

This is our first experience with a tankless system and we are not big fans. It takes forever to get hot water to our sinks! And yes we can find things to do while it’s warming up but the loss of gallons of water down the drain is problematic. Plus sometimes you just want to quickly wash your hands and be in your way. My husband was just out walking in our neighborhood and ran into an employee of the gas company getting a new house hooked up. He mentioned to him the issues we are having and it is his opinion that the tankless heaters The Villages are installing aren’t good quality. He said if it were him, he would upgrade to a more efficient one since the cost of a new one would be made up in 5 yrs. We may consider it.