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Does a tankless water heater save money?

By FPL Expert

Asked on: October 3, 2011 by James D., Fort Myers Beach

Will I save on energy costs by replacing my water heater with a tankless model?
Good question, James. The cost-saving benefit of replacing your traditional water heater with a tankless one is often overestimated. For most people, the most attractive benefit of a tankless water heater is that it saves space. The downside, however, is that tankless water heaters use a significant amount of power. This will likely require you to upgrade your home’s electrical wiring since using one tankless water heater for your entire house can draw more power than nine central air conditioners! Here’s how tankless water heaters work: Tankless water heaters (sometimes called instantaneous heaters) don’t have a water storage tank. Water is heated as it passes through a compact heating unit. In reality, the only savings a tankless model provides is the elimination of the heat loss. These losses are around 7 percent of your total water heating energy use depending on the age of your existing water heater. Since water heating represents about $20 of the average FPL bill, the savings for a tankless water heater would be less than $2 per month for a typical customer. Another thing to be aware of with tankless water heaters is that the water temperature could start dropping if two showers were in use at the same time. On the other hand, if there is only one shower in use, the hot water would never run out. To learn more about water heaters, visit www.FPL.com/waterheaters.

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Comments [178]

  1. Dave

    I am considering changing out my hot water heater to a tankless electric unit. I am using it in a condo that is rented out several moths of the year in the winter and weekly during the summer. The unit is rented about 25 weeks per year, the rest of the time it is vacant. Seems wasteful to be heating water in a tank when no one is there. Your thoughts.

  2. Herbert Valhuerdi

    I reside in a condo I have a 30 gal water heater and with on/off switch I use the heater for 15 minutes a day. Can I save with tankless water heater.

  3. Gary Lostak

    I would like more information on a tankless hot water heater and it’s rebates.

  4. Hot Water System Repairs

    Thanks for share…. It’s really helpful….

  5. Susan

    I’m thankful for having our Orlando Electrical Contractor ever since I come to notice our bill lighten a bit, but is there any other way how to save energy and money?

  6. Patrick eckenrode

    Hello, I purchased a EcoSmart 2700 instant-on water heater. Is there a Florida FPL rebate? Thanks in advance, -Pat

  7. Heating System Repair

    Nice blog.

    Thanks to share this type information.

  8. Rohnert Park water heaters

    Nice post and rocking shared to water heaters

  9. John Small

    The response to the comments about tankless or instant hot water, raised an additional question for me. My water heater is located at the back of my two-bedroom condo in what would be the closet for the rear bedroom, which I use as an office. The water has to travel approximately 40 feet to reach my kitchen, which is located at the other end of the condo, and about half that distance to reach the shower that I use, which is outside of the secondary bedroom, where I sleep. It seems to take a long time for hot water to reach either of those faucets. Is that a function of the water heater being inefficient, as opposed to the tankless hot water system. If the tankless system is more efficient for creating “instant” hot water, it seems there would be additional savings that would show up on the water bill, not to mention the conservation of a very precious resource.

  10. Alex

    This guy could not be more wrong, that a tankless can use the same as “nine central a/c units” are you crazy. I have been to 10,000 sq ft homes that do not have 9 a/c units and you want to tell me that one tankless with use that that much power.. I would do some more research


      I disagree with Alex’s comment about the tankless water heaters. I moved to Florida 12 years ago. The condo unit had an old 30 gal. electric unit on it’s last leg. Being in the hardware business, I researched the tankless heaters. I installed a 220 volt unit, using the same wiring from the old
      heater. I live by myself, and my hot water use is mostly one shower a day, (warm not hot water ) and a couple of loads of dishes in the dishwasher, and maybe one load of white clothes few times a month. My electric bill was average $100. After installing the tankless heater my electric bill went down 30 to40% ! I was heating water 24 / 7 ! Using it 10 minutes a day.
      How can that be energy smart? My yearly bill went down a total of 29%. I have two showers. We are able to use both showers at the same time.
      The STUPID remark about the water heater using the NINE times the amount of electric is STUPID!
      He did no research. That would calculate to the heater drawing 270 amps of power, with each AC unit drawing 30 amps of power. The heaters have multi elements. As your need for hot water goes down, the number of elements turn off. So you may start with 30 amps of power draw, but the unit senses the need for less hot water and turns off as many of the elements as needed to save even more power. Keep in mind most people don’t use straight hot water to shower. You would burn your skin. My heater heats the water to 130. So I use a mix of hot and cold water. I can’t say enough good things about tankless heaters. Consumers reports did a terrible review when they did the tankless water heater.
      Something else nobody mentioned. Tankless heaters don’t build up rust and scale on the botton of the heater which further cut back on the power consumption, and the life span of the heater, the bottom rusting out.
      Come on people think about it! You’re heating water for 23 hours for 1 hour ( max ) of use.
      Not to mention all the space you pick up in the
      closet or laundry room!

      By the way the guarantee is longer than most gas or electric heaters. IF you need to replace the unit, they will send you a new unit. You send the old unit back to them. They are VERY eash to replace. I have tankless heaters in my rental units, and in my own 3,000 sq. ft. home. Shop
      the internet for the best prices. You won’t be sorry. The gas units are great too. My friend has one, and his natural gas bill has gone down

  11. Carlos

    Your comment on savings is completely off, Independent National Testing Laboratories studies show saving in the area of 38-42%, not including HEAT LOSS which accounts for another 15-20% savings. This is the problem with supposed Energy Experts. They are no experts at all. Now keep in mind that FPL would not be very happy in loosing revenue on water heating since this is on average 20-25% off a households electric usage.

  12. Juan

    For Florida I recommend conventional water heater. Why? After so many years using conventional has proven that during times of hurricanes and long periods with power failed, the conventional works better for me because storage a great amount of hot water. The new and “improved” “tankless” are not able to storage hot water, making them useless during the unpredictable Florida weather conditions.

  13. Benicio

    I beg to differ, you are so wrong it isn’t funny. Well you are right if you go to those big box stores and pay for an overpriced under-engineered piece of crap… I’ve put two tank-less w/h’s in two different households in the past 9 years… Bought them on ebay, for $300 each, made in America by Americans… If you have 220 to the spot you mount it to, anything over 11kw will supply a 2-3 bedroom house… granted you can’t take two simultaneous showers with these units but my family never ran out of hot water and my electric bills went from $200 p/m to $120 p/m easily! And they are still running and working 9 years later… So it’s ludicrous to suggest you’ll be paying for them 10-15 yrs later… They More than paid for themselves in less than a year.

  14. Tankstar products and installation system

    If you don’t have water heater in your tank, it can be a less money in installing it but in the long run, you still boil the water in order to get heated in other way.

  15. los gato Plumbing

    It’s really great to post my comments on such a blog. I would like to appreciate the great work done by the web master and would like to tell everyone that they should post their interesting comments and should make this blog interesting. Once again I would like to say keep it up to blog owner!!!

  16. Express Water Heater

    Those reasons alone are good enough reasons to not go tankless. In addition, there are many parts on a tankless that can go bad. And they do go bad. Repair costs plus installation and the meager savings does not pay.

  17. Al

    Thanks for the advice. I was looking into installing a tankless heater but now since the saving would be so low it doesn’t seem worth it.

  18. Steve

    I have worked in the engineering department of one of the three biggest hot water heater manufacture in this country. Tankless water heaters are a niche product for those who do not have a lot of space. Sure they do not use any energy when not in use, but when they turn on, their energy efficency is a little bit above an old wood fireplace. High upfront cost and limited hot water delivery and you may need to upgrade your gas meter to handle the gas consumption rate when it is on. Cover story several years ago on Consumers Report. Tankless water heaters should NOT be considered a green product!

  19. ed de rogatis

    Thank you i will stay with my regular water heater your coments were very enlighting sincerly ED DE ROGATIS PS I HAVE BEEN A CUSTOMER 36 YEARS

  20. fred miller

    i have a mobile home and looking to replace my water heater with a tankless one ,on the electric its not a problem,because only getting a smaller design that does use to much current
    i have water heater at 120 volts and draws near 20 amps
    will i save money on a tankless type

  21. Donald Nelson

    How much does it cost on an average to install a tankless water heater system? How much power does it take? We are a family of two and we have a 2 bedroom 2 bath condo.

    Thnk you

    Donald Nelson

  22. G

    I have toyed with the thought of getting a tankless water heater and since I need to have my kitchen remodeled, I was going to have it done as part of the project. However. I have a pool and the back of my house faces south. I have always wanted to get solar panels to heat both the pool in the winter months and use it for hot water to bathe.

    Are solar panels cost effective? And what would be the pros and cons of installing them? ie insurance premiums and possible roof damage.

    My pool is 25’x20′ and avg of 4.5′ deep. I live in South East Florida


  23. kareen torgersen

    never heard of them. interested in the function and certainly the cost. i am a renter but have been discussing the heat loss for a while with my landperson. please more info…

  24. MAsh

    How about using GAS tankless water heater instead of Electric. How does it work and what are the advantages and disadvantages.

  25. John Madden

    How about ‘natural gas’ tankless heaters instead of electric! I have in my summer home and works great. Electric rates are very high everywhere in the country.

  26. Donald Winkler

    How about Natural Gas.?Or Propane.Is there a Savings?

  27. Lionel Dejour

    I have been planning to insulate my attic in order to save energy.Since it is so important now-a-days for everybody to save energy,does FPL have an incentive program to motivate and help his customers meet the cost of insulating an attic?

  28. Fatima Herrera

    Hello, Mr. Muccio:

    I am confused with your explanation above. I understand you say that to run an electric water heater is like running nine central air conditioners at the same time, and yet, it saves about $2 per month from the electricity usage that normally comes from the water heating tank.

    Are you saying that in the end it is more expensive to have an electric heater since the use of electricity increases by nine a/c units, even though the use of water heating decreases?

    If so, seems to me a water tank is more feasible. Although I did get my tankless water heater for storage reasons.

    Thank you,

    Fatima Herrera

  29. Constance Paciga

    I installed a tankless water heater and I agree with the expert not much savings if any with the electric bill but a little savings with the water bill, I do appreciate the added space in my laundry room. I do not run out hot water while showering now which is a good thing especially in the colder months.

  30. Constance Paciga

    I installed a tankless water heater and i agree with the expert it really does not save me much on my electric bill but I like not running out of hot water while taking a shower in the winter months. I have seen a slight savings on my water bill. I am sure glad I switched! I need the extra space in my laundry room.

  31. Karl Holtkamp

    What about a tankless gas water heater. No additional electric is needed. Gas is supposedly more efficient than electric.

  32. Robert DeRoner

    Your answer failed to clearly address the power usage necessary to maintain the temperature in the tank when water is not being used 24/7 365 days a year. On a yearly basis I would maintain that that usage is significant and over time would offset the cost of a tankless water heater.

    We are a small family of 2 and each shower once a day. Me wife works and I am out of the home more than I am in it during the day. We wash clothes in cold water and run the dishwasher at most twice a week. The amount of hot water used to wash our hands preparing meals and at other times during the day is relatively insignificant.

    You need to clarify your statement about the saving of $2 a month by indicating the family size that savings represents.

  33. Dick Hopp

    FPL’s reply neglected to mention the potential savings resulting from not maintaining a volume of water heated 24×7 when hot water is actually needed only a small percentage of that time.

  34. Larry Quinlivan

    How can I calculate how much solar power I need to replace 80 to 90% of my power needs?

    I read about great advances in solar power. Is it generally cost effective on a residential basis?

  35. Frank

    what about natural gas instant water heaters? Are they more efficient or less costly to run

  36. carol hjill

    what about the cost of water that has to run and is lost until hot water gets to you on a city system or the cost of electricity to run the pump for that cold warer that runs down the drain on a well system? what are the advantages/disavantages of the individual on-demand water heaters under each sink. I have had the pleasure of using these in and it is truly instant hot water with no waste. I know they come in 120V as well as 220V varieties.

  37. Barb

    I have a tankless water heater. I have found it takes quite a bit of wasted running water before the hot water actually gets to my faucet and the farther the faucet, the longer it takes. I also noticed if I’m washing dishes by hand, many times the hot water runs out for awhile and then comes back. This is annoying.I don’t think I would invest in another tankless. Granted once the hot water gets to where you need it, it is hot, however the wait and the waste is annoying.

  38. Abzal Mohammed

    Will FPL do all installation for the switch over to
    Tankless water heater or do I have to hire a contractor?

  39. michael

    Thanks for the info … though I would like to know the savings if you figured in the cost of the water/sewer costs while I am waiting for the hot water.

    1. LARRY


  40. Michael Garcia

    Ive given thought to installing a hot water instant heater but have been told living on miami beach would give me problems with corrosion and the device would a shorter life than a hot water tank.Thank You

  41. Margaret Warwick

    We are snowbirds and our Florida home often sits unoccupied for several months. Any suggestions on what we should be doing with our air conditioning, water heater etc when we are not here. We usually leave our refigerator running all the time. It seems like everytime we return our power has been off and our clocks need to be reset. Thanks for any help you can provide.

  42. BETH


  43. Norma Irvin

    Our one bathroom is far from the garage where our hot water heater is. Therefore we waste a lot of water waiting for it to get home. Would the tankless water tank be worthwhile in this circumstance.

  44. Mollie

    My interest would be with the tankless water heater is to save energy and save money and not just saving space. This is not happening with the tankless water heater.

  45. Vasquez Adelina

    Need to know where to file the form for $1000 rebate for Tanklless water heater thank you

  46. John Walsh

    Question. Do you lose water pressure when using a tankless water heater?
    I assume that the tubes in the tankless are smaller and don’t provide the same level of pressure. Right?

  47. Doug Dunbar

    How about the case where the home is a vacation home? It seems like it would be better to use this kind of heater, because it doesn’t need to be drained at the end of the season, as well as the initial filling and heating at the beginning of the season. You don’t have to worry about turning the power off all the time when leaving at the end of the season, because it only heats when there is a call for hot water.

  48. Herb Hanke

    Why does FPL wantus to use tankless to save energy, from what i read here it does not do that.

  49. Howard Korenman

    How much would I save if I install a propane tankless water heater that would be plugged into a 110 outlet?

  50. Jackie

    Wish I would have read this before installing my tankless water heater 2 years ago. Now I understand why I never saw a difference in my bill…next time i will make sure to do research before spending $600 -lesson learned!

  51. Steve Von Jasinski

    I disagree with your sumation on the benefits with a tankless water heater. You are spot on about most Florida houses being under amped/wired for a electric tankless unit. Where I disagree with you is the heat loss statement. My observation of Florida homes is the loss of heated water from the LOCATION of the storage tank. Many are located as far from the most frequently used Hot Water locations as possible, ie. garages. It is this waste of water, draining pipes to deliver heated water at lavs and sinks, then reheating the storage tank volume that is saved with a tankless unit, RELOCATED/POSITIONED closer to the end use locations that can dramatically reduce energy costs. My wife and I recently purchased a second home in Ft. Myers area, have replaced the heater with a highly insulated unit, and installed a in-line supply disconnect. Next trip down, I am installing a “tankless” unit underneath the lavs. Only the large volume use appliances, showers, dishwasher, etc. are on the primary water heater system. This should reduce energy waste as much as economically possible from the “HOT WATER” equation.

  52. Mary Jean Wampler

    How about a small house with no dishwasher and only one shower? Occupied by only 2 persons.

  53. Arthur Hagen

    If the water temp drops as it does in the winter, you may have to get use to a cold shower. The tankless water heater only heats the outlet water to a max of 45 degrees over the inlet. A shower of 70 degrees is not very comfortable. I found this out 2 years ago, and initially thought my hot water heater had gone bad.


    1. wayne

      I couldn’t agree more. If you introduce a timer in the mix, your savings would be just a good, if not greater than all that energy it takes a tankless to quick~heat 8 to 12 gallons of water needed for a shower.

  54. Tony Stinnette

    I just wanted to make a quick comment about tankless water heaters. I own a whole house natural gas tankless water heater and the only electricity that it uses is a single 15amp circuit that is used for the onboard control system of the tankless water heater. So, you don’t need to rewire your house and it doesn’t use a lot of power. The assumption above, which isn’t stated, is that the tankless water heater is all electricl with no natural gas. I do save about 30% on my natural gas bill compared to my previous tank water heater.

  55. Berson

    Then why do the tankless water heater companies claim, 40% savings?

  56. wm hayden

    It may be true if you are applying changing out your old electric heater but not so true if you change out to nat. or propane units. I just installed a 160.000 btu unit and I expect to save half of the cost of the electric each year and a cost of replacement in about four years.

  57. mary

    I have been looking at these water heaters for a while, mainly at the home shows; they say that you save a lot of money with them. I thought it would be beneficial to me as I don’t use a whole lot of water any more, so I am asking if you think it would be.Also I have another question about a humidstat. I have a blue light on the air cond. does the hum. do the same thing. Thank You

  58. jose

    i have my tank water , i want to know if i put off tha tank and just put on when i need warm water for the shower , can i save money in my bill if i use this method?

  59. john jankus

    tank less hot water heaters for whole house application come in natural gas or propane and are much more economical than electric water heaters.

  60. Thomas Sheaffer

    There is another benefit of a tankless water heater that you don’t mention. If your main water heater is located a long distance from the point of use, a tankless can save water.

    For example, one of the bathrooms in my house, the one I use most often, is located all the way at the opposite end of the house from the water heater, which is in a utility room off the kitchen. Every time I wash my hands or take a shower in this bathroom, I have to let the water run forever before it gets hot. If I had an instantaneous heater there, I would save a lot of water that is currently being wasted, and also have the convenience of not having to wait.

    If I did that, I would connect the tankless heater to the hot watr line. Then I would get instant hot water, but for longer use in the shower, the tankless heater would be fed from the main water heater and would not use much additional electricity.

  61. Brian

    I completely agree with Craig’s assessment. I considered installing a tankless water heater when it was time to replace my aging natural gas storage water heater. I’m a DIY’er… and even performing the installation myself, I found that the cost of a tankless water heater that could run two showers simultaneously would not pay for itself.

  62. Jeff Eyke

    Is an electric dryer more economical than propane?
    What about water heater?

  63. Douglas Cregar

    Question: Will a solar water heater significantly reduce the cost of heating our community swimming pool and repay the cost in a reasonable time?

  64. Lorraine Bolton

    We have had a tankless hot water heater for three years. The first one was too small so we had a larger one put in. Also the electric had to be upgraded at the circuit box which was not costly. So far it has worked well. Plenty of hot water. But you are right, two people can’t shower at the same time. The water runs differently. You can but the water seems slow. We never have seen an inconvenience of any kind yet.

  65. Walter Wood Sr.

    What about the Natural Gas Tankless Water heaters?

    Will they save energy?

  66. Mike Bauduin

    You have not considered that a lot of water would also be saved while waiting for the hot water to get where it is going. A local tankless gives you instantaneous hot water. The downside is putting units near the area of use. This is more easily done in new construction as opposed to a retrofit.

  67. Gloria Palmer

    I just read about tankless water heaters on this site and when we moved in here we had one, does it make any sence to replace it with a new gas or electric water heater, we have propane for our stove and perhaps the tankless? Possible even? What is a normal average bill for a househld of 3 adults?

  68. Patricia Nye

    THANKS for this info. Was considering buying one
    but now I will not. Too expensive! AND I obviously already have “room” for a hot water
    tank in my home. Appreciate the advice.

  69. Celida Hernandez


    My question is: If I set up my A/C to turn on/off automatically, will it save money during the FL winter time when the air is cooler outside?
    We set it when we are not in the house at 78 and at 73 when we are in.

    Should we turn it off when we leave the house on the weekends or leave it at 78 or even 80?

    What is the best temperature to have when we are not in the house?


  70. Douglas Walker

    This is an incomplete answer, and it makes sense that the power company would be incomplete in their answer.
    1) most tankless heaters are gas, not electric, and gas is more efficient and cheaper. so in actuality you would save much more. It is a well known fact that converting electricity into heat is the least efficient way to create heat.

    2) A traditional tank heater also heats water all the time, if you are out of town for a few weeks that tank is still heating water and holding it, so while technically heat loss is the culprit you could be heating water several times before using it.

    1. John

      (2) When you are away from your home for an extended period of time turn off your tank water heater to save electricity. Put In a timer on your heater for use when your not away.

  71. Daniel Hoffman

    As the article didn’t address the number of people in the household, how were the conditions control for; (ages, number of showers, loads of laundry, length of time in months your study was conducted, summer or winter, etc.) actually usage can not really be determined for an energy savings study. What was the actual pay back – new energy efficient water-heater vs tank-less purchase cost an usage!

    So based on my own usage, single retired male, & (using the FPL electric bill) I’m saving approx. $50.00 to $60.00 per month using a tank-less water heater after paying for purchase/install.

    Note: my tank-less water-heater was purchased off of eBay for a cost $225, cost to install was $200. This included new wiring, 60amp circuit breakers and plumbing. So after eight months I actually started saving the $50.00 per month.

    Please post your response so customer can make an informed decision with all the facts.

  72. Michael Frueh

    I do not agree with Craig on this one. The real savings of a tankless water heater is that you are not wasting electricity, (or in my case, gas) by keeping water in the tank warm 24/7. Electricity

    That being said – as a father of 4 boys, the tankless water heater is invaluable in that you will not run out of hot water when you are last in line for the morning shower…

  73. Rodney M. Doucette

    Thank you FPL for your keeping all of us in tune with pros and cons especially insofar as a tankless water heater is concerned. Your input is most beneficial and much appreciated!

  74. Dennis Bessette

    Please differenciate between an electric tankless water heater and a gas fueled type. The cost of installing a gas fueled heater depends on whether you already have natural gas or propane on site but many fuel suppliers will give discounts on the fuel tank, piping and initial fill-up in exchange for the fuel account. You also can look for a lower electric bill and in many cases the load reduction on your electrical service may allow the home owner to operate with an older service rather than upgrading to extend load capability or available circuit breaker space. Even though switching to gas lowers income to the electric provider, it also removes a huge demand on a aging electrical grid and helps smooth out big peak demand spikes caused by water heater use. Another benefit of having an available propane source is that an on-site supply is immune to power failures and allows a home owner to consider a standby generator and a hook-up for the gas grill that can come in pretty handy if the power grid is down due to a damaging storm.

  75. bruce tonnessen

    i think there is one other advantage, and that is the elimination of the possibility of flooding due to failure of the the water heater tank. this is significant in multistory and multi-unit buildings. my neighor’s water heater failed a few years ago, and the flood did some damage to adjacent apartments; however, it did a lot of damage to the unit directly below.

  76. George Vitale

    Your response is really not valid. You must also include other forms of energy such as propane and natural gas. Thes are both available here in Florida and much less energy will be required to heat water using these two forms. Also what about the energy used to keep the tank of water hot at the time of non-use?

  77. Elizabeth Dillon

    My husband and I live in a 2 bedroom, 1 bath apartment. The living room area has a small kitchen walled off at one end. We need more storage area and I wondered if an tankless electric water heater could replace a tank giving me room for a small washing machine. I always wash with cold water. The apartments have laundry facilties but I don’t like washing after others. All my appliances are about 1 year old except the dishwasher that I just installed. I only run the dishwasher 3 times a week at the most unless I have guests. I shower in the morning and my husband early evening or late afternoon. It is difficult to run new wiring as I’m on the first floor and we have cement block walls. I didn’t know if it would be possible to install a tankless or if we would have enough hot water.

  78. juan badell

    I run my central a/c fan all the time but I keep the thermostat 2 two 4 degrees warmer than I would if it was set on auto. What saves the most electricity, running the a/c fan always with the thermostat set higher or having the a/c fan on auto with the thermostat set lower?

  79. Joseph Kalman

    Thanks for precise info. It’s quite a disappointment, In a nut shell, electric tankless water heater means large expense up front and saving possibly $2 a month. Financially it means that it will take about 10 years to recoup the cost of the investment. 10 years could be also life of the water heater. For an average home owner this is a bad deal.

  80. donald bitler

    Would installing solar reflective films on the East and west facing windows of my home save energy? Some manufacturers claim they also add to the insulation value of the windows. I already have High efficiency double pane windows that are not tinted.

  81. Thomas Camps

    My interest in tankless water heater was that our master bath is located a distance from tank water heater in garage. It takes considerable time to run hot water to the master bath both for the shower and lavatory. It seemed the tankless heater may solve the shower problem but not the lavatory problem of hot water.

  82. CJT

    In my case the five year old 40 gallon Hot Water Heater sprung a leak and had to be replaced in 2008. After reviewing my options I chose to install a tank-less electric heater. My house has an electric furnace and the service entrance panel is adequately sized. Otherwise I would have considered a GAS unit.

    I am on well water and unless you feed the heater consistent water pressure you don’t get consistent temperature. I was then forced to correct my well water delivery problems but that is another story.

    I installed the system myself not more than ten feet from the Electrical panel for about $800 and my electric bill was reduced about $20 a month. Considering the $400 increase to change to tank-less, it took almost two years to pay off the added cost. If it was professionally installed it would have been a longer payback period but still worth the price.

    The PROS: endless hot water and assumedly less likely to corrode and leak from bad water.

    The CONS: the cost for and to install the tank-less unit. Excessively Long showers are not cut short with a tank-less system. :)

    Your mileage will vary on the electrical savings.

  83. Josephine Cracchiolo

    I have a tankless and I love it. I never run out of hot water and even when 2 showers are going at the same time the water was just fine.

  84. Bill Osborn

    I worked for Illinois Power, starting back in 71. One of my first jobs was advising customers on electric and gas use. We strongly advocated adding an insulation blanket to water heaters, and had facts to show they quickly paid for themselves. We had numerous other energy saving alternatives for our customers. Guess history is repeating itself.

    On another note, two years ago at the bottom of the housing bust, we looked at numerous houses in the Cape Coral area for a vacation home. Having had the position noted above and having dealt extensively with insulation versus bills, I was amazed at the lack of insulation in most all of the houses we looked at, and the non energy efficient windows they had. For several reasons we did end up buying a new condo, which being a middle unit has very low bills. We plan on selling our home here in the Peoria Illinois area next spring (home prices here have not been affected due to the proximity of Caterpillar and State Farm and colleges) and buying a retirement home somewhere in the Cape Coral to Naples area. Rest assured I will be closely looking at the home construction and insulation used along with the windows.

  85. Frank

    You are talking about electric tankless heaters and not gas units?

  86. becky

    How about if you go from an old fashion gas tank water heater
    to a gas tankless water heater?

  87. Joey Schwab

    I agree 100% with your answer and we have to explain this to our customers often due to the marketing associated with tankless heaters. However, while I understand that your answer relates to “ELECTRIC” tankless heaters, it would be good to clarify this. Tankless gas heaters are much more efficient than electric and will realize more cost savings associated with their operation.

  88. Terri

    We’ve been wondering about the same thing….we have a two water heaters, one upstairs and one down. The upstairs water heater rarely gets used. It is over 10years old, and although we have not had any problems with it – it is in a very tight space and difficult to reach. We are thinking about having it replaced prior to any problems – we were contemplating replaceing it with a tankless…now, we know. Thanks!!

  89. Tony

    The answer applies to an electric tankless water heater. What about a gas tankless water heater?

  90. JOE


  91. Dave McLinn

    My family used propane fueled tank-less water heaters for 10 years in New Hampshire. They required maintenance and were temperamental.

    The greatest benefit was unlimited hot water when the home was filled with guests.

    The greatest disadvantage was that restricted water flow shower heads reduced the temperature of the water flowing through the system.

    Timers on electric tanks are more cost efficient (water & electricity usage) than tank-less systems.

  92. Chuck

    At Century Villiage they have only 100amp service can you install a tankless hot water tank is it legel & safe? There are people that are selling a tankless hot water tank at Cenury Villiage. Is it safe?
    Thank You

  93. Jeff R.

    Could you use an instantaneous heater in combination with your water heater and keep your water heater at a lower temperature, say 90-100 degrees? It seems to me that the heat loss in the water heater tank would be less, and the electrical energy needed to instantly heat it to the desired temperature would be reduced.

  94. David Van Kleeck

    It would be helpful to have your input re: using a tankless water heater just to service the master bath area, particularly cost comparison and the recommended range of capacities. My whole-house water heater is on the opposite side of the house from the master bath, and is closer to the kitchen and 2nd bath plumbing. There is noticeable delay and heat loss in getting hot water to the master bath as things now are.
    Thank you for your attention to this.

  95. Mary Ann

    With a tankless water heater, wouldn’t I save water because I would not have to run the water so long. In my bath room, which is rather far away for the water heater, the water runs and runs before the hot water arrives.

  96. Mike

    I save a lot more than $2 per month with my tankless water heater. I don’t know where you get your figures!

  97. henry molloy

    For tankless hot water I have to upgrade my service.
    Uses more power than 9 A/C’S and I save $2. a month.
    Thanks for the honest comparison between hot water tanks.
    Not worth it.

  98. Vince

    If you address the same question but use a natural gas water heater, the savings are substantial!! Todays natural gas tankless systems are perfect for Florida’s ground water temperature. Make sure to size the tankless system for the number of “hot” requesting sources. I have a 3100 sq ft home with 3 full baths, dishwasher, washing machine and laundry tub in the garage. I have a Rinnai 7.4LSI direct vent system. After replacing the conventional tank, the electric bill went down by $75.00 a month and the gas bill is $15.00.

  99. Robert E. Hanson

    My question is: If one has a long supply line from the hot water heater to the kitchen spigot and dishwasheer, should one consider having a small auxillary hot water heater under kitchen sink to heat water from cold supply. Right now we waste a lot of hot water getting it to the kitchen.

    Thanx for your reply!

  100. Dave Frank

    What kind of savings can I expect by placing my 50 gal. electric water heater on a timer and having it off from 9PM to 7AM ?

  101. allabn black

    I dont think this is a fair statement, i have a Gas tankless heater, the only power it uses is for the piezo igniter, and we use it in 2 showers at once quite often, with no noticable differance in the temp of the water. I believ it is a very good way to go, to save a little electricity, and my gas bill and my elect bill are both together less than severaal of my neighbors electric bills who live in comparable houses. If you are going to discuss tankless heaters, you should represent all of the options.

    1. Earll Sloan

      You’re correct in all respects, but one.
      As a rule dishwashers are connected to the cold water supply, not hot. Check your installation, and see if that’s not correct.

  102. Robert Griffin

    Electric tankless water heaters are not practical – but you didn’t give the whole story………..
    Gas tankless heaters are practical and save money. I spoke to the FPL rep at the Home Show recently and he echoed exactly what you reported but we both agreed that tankless gas powered was the practical solution.

  103. Russell W. Owens

    Using a gas fired tankless water heater saves lots and lots of energy. Only a little spark is needed to light the gas.

  104. Kathryn Summer

    I turn off my hotwater heater after taking a shower and turn it on 15 minutes before taking a shower or washing clothes or using my dishwasher. By doing this, it has reduced my electric bill significantly. My questions is…will this cause damage and excessive wear and tear on my hotwater heater?
    Thank you

  105. Ilse

    I have a tankless water heater and I love it. It has saved me money
    on electricity. I will never go back to the regular water heater.

    I have no problem with having enough hot water. Just wanted you
    to know they are not bad like you make them out to be. I have
    used one for over 15 years.


  106. Kathleen McCall

    I love utilities giving these hints. I lived in Upstate New York for 44 years. I read the inserts religiously. I was one of the first people to buy the energy savings light bulbs for the upstairs bathroom lights. I paid around $26.00 each. Did it save me money, oh ya!!. I bought them either in the late eighties or early 90’s. At this price, they still saved me money. Look at how low my energy bills are, unbelievable. There is no regular light bulb in my house. Won’t spend the money on a tank less water heater either. Thank you!

  107. Patricia Marshall

    I live in a condo unit, in cocoa beach. The funny joke in our house is when we want hot water in the kitchen it goes to every unit first before the kitchen. It is a large condo with 3 full bathrooms. My question is is there a small tankless system that works well if we installed near the kitchen sink. And is not costly monthly.
    I feel I use so much wasted water waiting for the hot to get to the kitchen.
    Rest of the house(condo) is ok showers, etc

    1. Miguel

      Your best choice is to install small area tankless water heaters as they do in some hotels, that way you will have instant hot water at each station plus more savings in heating the water.

      In my house I have a tankless water heater that serves all the areas plus three bathrooms, it takes a minute or so to get hot water in the bathroom since the water has to travel from the garage all the way to the bathrooms area, same thing happens with a tank water heater, it takes a few minutes before you get the hot water at the other end of the house. All in all I like the tankless, basically because I can use the extra space, I do not need to worry about replacing the tank when it gets rusted, and never run out of hot water, problem I had with a traditional tank water heater.

  108. David Van Brunt

    I suspect your answer to this question about energy savings of tankless vs. tank type water heaters assumed an electric tankless water heater…Am I correct? I went to a gas tankless heater. Between the discount offered by TECO and my reduction in utilities, I figure my pay back is under three years.

    Your thoughts please.

  109. Towar Bates

    Definite savings in space and for one person the “tankless” works very well.

  110. dallas hilliard

    I take exception to your assestment of the saving of a tankless water heater. I move to palm bay and for two months had a regular water heater. When I switched to a tankless my FPL bill dropped $40. I have a 4.5 GPM water heater and is able to run two showers and dishwasher without running out of hot water.

  111. j vento

    i have a gas tankless water and i do save plenty you should have compared the two

  112. rlee

    not only is the only saving the heat that is lost in storage while you do not use it but to the extent that you turn on heat in your house or apartment anyway, during the winter, which happens for two or three months per year down here, the heat is not being lost wastefully. It is heating your house. the savings up north are even less. also, tankless water heaters (demand heaters) depend on consuming large amounts of energy over a very short time, and all the parts go from ambient to very hot over very short periods of time, so the parts work, expand and contract and theoretically would not last as long as contraptions that do not undergo that stress.

  113. april mast

    There is one other huge reason to go tankless, when living in a condo or villa the worry about the water heater leaking which is quite common in Florida is thoroughly removed. saving thousands, thousands of dollars in repairs not only to your home but the neighbor below or to the right or left of your villa. I went tankless and not only do I have a huge closet now, I do not worry about flooding my wooden floors or my neighbor’s villa. I have not found a significant drop in temperature when I have grandchildren showering or guests using the second bathroom and I bought a lightweight tankless model. Something to think about, thank you for bringing the subject up.
    PS the installation was 450 for the plumber and 450 for the electrician and 450 for the tankless online. I think I already have a great return after one year and I can leave my home with no worries.

  114. steve

    I believe your calculations are wrong. I installed a whole house electrical tankless water heater and immediately realized a savings of approximately $40 per month….The unit and installation have long since paid for themselves through these monthly savings.
    There are many variables of course, but to say across the board the savings don’t warrant the installation is wrong.

  115. Dave Caccamise

    What about the pump system that circulates hot H2O to all outlets at timed intervals resulting in instant hot H2O? You still ahve a hot H2O tank but no waiting for the H2O to get warm at your end.
    Thank you.

  116. Mark Stokes

    If we were to get a tankless water heater does FPL install it and how much does it cost (Mark Stokes, Punta Gorda).

    Thank You

  117. craig strain


  118. bruce

    “Averages” are just that, and there can be significant variation from one home to the next. If you have a family of 4 or 5, taking showers, doing laundry, washing dishes… you use a lot of hot water, and Mr. Muccio’s assessment is correct. Stick with a conventional heater. If you live alone, eat out alot, often shower at the gym… you really don’t need to keep 30 or 40 gallons of water hot all the time. A 60 or 70 amp demand heater would be a good choice. It’s also a good choice for a vacation cabin or condo that is occupied infrequently.


    I love my tankless system……….and my FPL bill has reduced $20.00 to $40.00 monthly by the number of hot water users. I disagree with your energy expert.



  121. Lawrence Cornell

    I have wondeed about the savings with using a tankless water heater. It looks like I would save little or none at my age by buyunf a tankless. What specs. and size are recomended for a family or three or four a traditional water heater? Thanks

  122. Nancy Badian

    Thank you for your advice on tankless water heaters. I was totally misinformed by programs that I have seen on TV. Apparently, the tankless heater is not worth the money it costs.



  124. Charles W. Saarela

    We had a gas tankless in N.H..and it saved us money. we switched from electric. We love it here in Florida even tho it is all electric, we do love gas cooking. thank you for great service and rates Chuck

  125. Emiliano

    Another advantage would be that the water is heated just as needed. And that represents a consuderable savings.

  126. Jeff

    You are right and wrong, if you use a tank less ALL electric water heater, then it uses a lot of electric at the time it is operating, but we have 2 LP gas commercial tank less models in our house and it only uses electric to get the initial spark to light the gas, that’s it. I would not have anything else.

  127. Catherine Morse

    Thank you very much for this answer as I was thinking of going with a tankless water heater.
    But after learning that it uses as much power as 9 central AC units and needs a wiring upgrade and will not work if two water draws are in use at the same time causing loss of hot water to both I am sticking with my old water heater.

  128. jack white

    it sound bias and not accurate,why did you not tell your customers about the gas tankless,this could cause to question your next advice

  129. Thomas E Henz, PE

    I have been a strongly against tankless water heaters for many years. Many of my clients including builders have insisted on using them.

    The facts are; most tankless water heaters will not heat when water flow rates drop below 0.6 gpm. Current building codes limit lavatory flow rates to 0.5 gpm, assuming 50-50 hot to cold mixing, this results in approximately 0.25 gpm, hot water flow rate. This means shaving with cold water. One leading manufacture recommends removing flow restrictors, clearly a violation of our building code.

    I addition to varing water temperatures, the very high temperatures required to generate instaneous flow rates results in an accelerated mineral scale build up,
    This reduces the heating efficency resulting higher operating costs and less hot water. Most manufactors recommend flushing the unit with white vinegar for one hour every 6 months and perhaps evert month for restaurants. Flushing consists of disconnecting gas or electric, providing a pump and bucket to manually pump the vinegar through the unit. Who in the world is going to preform this required maintenance?

    In my opinion, the only place for one of the units is in an office break room for hot water for the sink.

    Perhaps the biggest reason not to use these units is cost, more expensive than standard tank type and expensive electrical or gas installation, I see no realistic return on investment.

    Stay with the now more efficient tank heaters.

  130. Darryl

    Thank you.

    We had been considering the “advantages” of changing our system.

  131. Jerry

    This supposed expert makes no sense. A traditional water heater has to constantly heat the water in its tank,Thus using power all day. A tankless water heater only uses power when its needed for intant hot water. I have a tankless and it has saved me over 25.00 a month. Please use true facts and not opinions when teaching people.

  132. Donna

    I had looked into tankless water heaters when I built my home five years ago. I determined that the cost of purchasing the unit, and the additional cost of upgrading my electrical wiring far outweighed the monthly savings on my bill. I installed a conventional heater, and since I am by myself, I turn it off for a few days at a time, only turning it on for about an hour to heat up the tank! I am way ahead of the curve on this one.


  133. Henry Rados

    I’m in and out of the shower,so i don’t much use hot water.It would be a waste of money to get a tankless water heater.

  134. Cary Engelhardt

    It’s amazing that electrical in Europe is significantly higher than here – however everyone uses tankless water heaters. I guess that’s just another area that Europe is behind us – Oh that’s right they are way ahead of us is almost EVERYTHING… It ONLY uses electricity WHEN it is needed – the water heater is constantly using electricity – also funny how you don’t even talk about Natural Gas Tankless water heaters…

  135. paul k

    Within the last two years the well known Consumer Reports published their findings and basically said tankless water heaters waste electricity with no savings on electric bills

  136. Mary K Baumslag

    The answer to this question is so limited. How would a tankless heater save money if it was installed in a summer houws/weekend house? My guess is that it would be significant and that for the weekend house one would not have to wait some hours for the water to heat as it would in a water tank situation where the heater was turned off when the owners were not in residence. Also,
    take a 35 gallon heater tank then add 3 teenage boys and you will discover that there is no hot water to wash the dishes after breakfast not to mention hot water for Mom & Dad to have a shower.
    No,this question needs a far more comprehensive answer than was offered by Florida Power & Light.
    I wonder why they did not see the flaws in their answer.

  137. Carl

    Another benefit to the tankless system is the elimination of the risk of a flood if the standard water heater leaks. This is a far-from unusual occurrence and the folks on floors below will be very grateful if you install a tankless system. We have one and we love it. Did not need any re-wiring, and we have never had a problem with 2 showers running at the same time. Perhaps if the dishwasher, the washing machine PLUS two showers were on at the same time it might be a problem, but that has never happened yet.

  138. fred deaver

    My neighbor, Mike Cook, who works for FPL in Naples, Fl gave me the same information about tankless hot water heaters years ago. You must train your people well.
    Thank you for the information.

  139. Kathy Campanirio

    But they save on water storage being kept hot over time Don’t they. I love mine tankless.

  140. Earl Skovsgard

    I have found that installing a timer on my conventional hot water heater saves some energy, I have it turn on at 6AM turn off at 9AM, turn on at 5PM turn off at 8 PM,–this scedule afford’s plenty of hot water when needed and does save some energy–Have a great day —Earl
    PS The cost of the timer + install is about $150.00

  141. Vincent A Bommarito

    Why not buy a Solar water heater and save $15.00 a month per person taking showers in the house / two people equals $30.00 dollars a mo. savings on your electric bill and R O I is two and half years,showers can be taken by two people with no drop of heat.

  142. sue

    Also, I learned after Hurricane Wilma and no power for 9 days, that with a hot water heater that we were able to have some warm water for showers for a few days. A tankless doesnt give you that.

  143. Mike

    I use a tank-less. Yes the room here in the condo is priceless. The tank-less gave me another closet and my tank-less has three elements and can handle 2 showers at the same time. I just keep the temp.down to what is good for a shower. Then only using the hot water. Why add cold water to cool hot water you just spent money on to heat?

  144. Darleen

    We replaced the regular hot water heater with a tankless water heater in our home in PA. We found that the water pressure was too high to allow time for the water to be heated. So we just put less pressure on the system and it works great. With 2 of us showering, A/C running and doing laundry plus the TV going practically non stop our highest electric bill was just over 60/month. That was down from over 100/month with the traditional tank water heater (which was about 5 years old). I can’t speak for anyone elses experience but I am now planning to change the system here in Florida to tankless. Hopefully it will work as well here as in PA.
    Thankfully, if not I have a plumber & an electrician in the family :-)

  145. Jeffrey Donner

    A friend of min had a very advanced expensive system installed, and he said the Problem was that it took a “long” time for the Hot water to start flowing once the Faucet/Shower was turned on. This does not sound viable for me…

  146. John E. Broen

    I realize that you took the electricity approach to the answer considering you are in a FPL message. However as a Snowbird who spends half the year in Canada, we here would only consider a natural gas tankless model. I have often wondered whether the economics would be different with this other source of heat.

  147. Kurt Markgraf

    Are you commenting on a electric or gas tankless water heater? Do your comments hold true for a propane powered tankless heater.

  148. Steve Clavette

    Your answer is not correct.

    When additional fixtures are turned on, the temperature at those fixtures does not drop, only the pressure.

    Another benefit that you did not mention is if you have a family of four and everyone needs to take a shower in the morning, a tank water heater will not handle the load (assuming the showers are taken immediately after one another). With a tankless water heater, you will NEVER run out of hot water.

  149. Ed

    We upgraded to a tankless and have no problems running 3 showers at the same time. We can now fill our garden tub without running out of hot water. It is also much more consistent in temperature. The space savings are a big plus to us. The down side is that it was expensive and required new wiring.

  150. Jerrry B

    This was great info. I was thinking of replacing in the future. It is great to get all the facts


    1. Marcel

      Well, the sad thing about the article is that they didn’t really qualify the claim. The largest draw from a Home Depot unit is the Tempra 36 at 36kw drawn. So running it for an hour costs 36kwH – Heating just 250 gallons of water with this unit (less than a day’s worth of normal usage for a family of four – though, granted it wouldn’t all be HOT) means you drew the same amount as your average neighbor does in 30 days. And you did it in just over four hours. Definately CAN cost you a BUNCH if you get a big unit. But its like saying “the extremely most expensive item you can buy costs more than the regular cheaper one.” ie. DUH!

  151. Steve Appelbaum

    I looked into replacing our 80 gallon HWH with a tankless a number of years ago. Since no vendor could give me output numbers when grandkids are in one shower, me in another and the washing machine going, I decided to keep the HWH.
    Hurricane Wilma knocked out our power for four days. Both my wife and I were able to take quick showers each day for the four days with an acceptable water temperature. That is not happening with instant hot water.

  152. Tom Conti

    Ref to tankless water heater: We have one but are unhappy when the weather gets cooler the water flow gets slower and the temp drops. I’m not sure if the unit is older (3-4 years) or if something might be going bad. Thanks

  153. Marion Suro

    The removal of a possible “flood” source is also significant, especially if the hot water heater is located inside the home.

  154. JoAnne

    I installed a gas run tankless water heater about 5 years ago hoping it would save me money. It didn’t. The cost of the gas overrides any savings I may have gotten on my electric bill. Honestly I don’t see any savings on electric either. I think the darn thing costs me more to run than my old water tank. As for the “instant” hot water – not true. We have to let the water run for about 5 minutes to get the cold water out of the pipes before the hot water actually gets to our faucets so we spend more money on water. Overall, a poor investment for us.

  155. Stephanie Safren

    I was so relieved to read your response about tankless water heaters, as I recently replaced my water heater with a traditional tank after experiencing a huge flood. As it was an emergency, I simply replaced my old water tank with a new version of the same but then wondered if I had acted to hastily and not bought a tankless system. Thanks so much for letting me know I made the correct decision.

  156. Jim

    You don’t address the use of propane or natural gas tankless water heaters. I think there is a significant savings and you are not keeping hot water in storage night and day.

  157. c_dub

    I recently installed one in my home and found out the hardway that if the tankless heaters have an issue, you have to tke them out send them off to be serviced and them reinstall them upon completion…. that was 4 days without hot water and an extra 400 to have it removed and serviced and reinstalled

  158. Jeffrey

    I replaced my 40 gal electric water heater with a 240V 18Kw tank-less unit several years ago. I noticed a huge difference in several ways.

    1)I live in a condo..by removing the 40 gal tank I gained a closet for other uses. I installed the tank-less unit in the attic, out of the way but serviceable if needed.
    2) We are total electric…my utility bill dropped by $20 dollars a month. No reheating the tank every time someone took a shower. No reheating the tank after doing the dishes.

    Heater supplies endless hot water for showers no matter how many users. So if you have a large family you will never run out of Hot water…ever. And as soon as you turn off the shower the power consumption stops.

    So in my opinion installing a tank-less unit is a big savings both in space saving and energy savings.

  159. ira

    why didn’t you mention a timer! we save at least $5 a month with one as opposed to without one.
    we have it timed for 30 mins twice a day.
    the water stays warm for at least 12 hours.
    timers are cheap especially if you install one yourself.

  160. Frank Gaylord

    It seems to me your response does not address a tankless heater at a sink or shower location distant from the hot water heater. Without that tankless heater water will be run and wasted until it becomes hot, which costs money. Please calculate the value under that condition.

  161. Ive Sauls

    You need to make the difference known between an electric tankless water heater and a gas tankless water heater. If you do that, you also need to make the difference known between using propane or natural gas to fuel it, because of the difference in price between the two fuels.
    There can also be discussions as to the size of the unit and the size of the household it would be serving. Obviously the greater the size of the household, or the greater the demand or frequency of use, will lean more favorably towards the use of a tankless water heater as well as a quicker payback on it’s initial cost.

  162. Ed Kuznar

    Craig, I installed a tankless water heater about 4 years ago and I enjoyed a noticeable drop in my electric bill-certainly more than $2.00 a month. I didn’t need to change the wiring, only the breaker to a 60 amp. I find your analogy to running 9 central A/C units hard to believe. It’s difficult to take two showers at the same time in any home with a tank heater because of the pressure drop. I’ll never use a tank again. Ed

  163. drsteve

    An unexpected problem is that even with the (expensive) electrical upgrade, if the outside temperature drops significantly,the starting water temperature will be colder, and the tankless heater has a greater temperature to make up for, and the water will NOT be as hot. [I learned that the hard way.]

  164. Paul P

    Outside the US, tankless water heaters are widely used and save a ton of money in a small household because they run on safe, plentiful, Natural gas.
    The Gas man comes once a week and takes any empty tanks and leaves one or two full ones. After a few months the man knows how much you use. Once a month he leaves a bill and you leave a check or cash under an empty tank. Cheap, simple, and friendly. Much too complex for us to do I guess.

  165. Kyle A. Fort Myers

    In my case I would disagree. We had a propane powered water heater that needed changing. We replaced it with a tankless water heater, the unit is now outside and freed up space inside. We have noticed a reduction in the amount of gas used over the last year. I understand this may be irrelevant to a user who only has electric available. We also got to take a credit of 30% of the cost off of our taxes. The heat is instant and never ending if the unit is sized right for your house. I would reccomend a gas powered tankless water heater over an electric one.

  166. Carl

    There is another very significant benefit to having a tankless water heater, especially for apartment dwellers, and that is the elimination of a possible flood if the water heater springs a leak. That has happened on many occasions and the poor folks downstairs get the worst of it.

  167. Michael Glantz

    A benefit not mentioned in Craig’s reply is convenience and additional saving if the conventional main water heater is located at a large distance from a point of heavy use.

    A tankless heater close to the point of use will deliver hot water very quickly, and less energy will be lost in the process. While it’s still possible to get instant hot water from a distant conventional tank by installing a recirculating system, that wastes even more energy.

    So while simply replacing an existing water heater with a tankless model has only modest benefit, adding a tankless heater close to a point of use (a distant kitchen or bath) provides fast hot water and some energy saving.

    In new construction, it’s desirable to locate the main water heater at a central point where it will have the greatest benefit, whether tankless or conventional. Tankless heaters have an advantage, here, in that they can take up much less space, and so be placed in a location where it might not be possible to put a conventional heater.

  168. julius accardi

    of course, replacing my water heater with a Gas Tank-less water saved me a tremendous amount of money, but FPL won’t tell you this

  169. Joan Rickey

    I believe a point you failed to make is that with a tankless water heater, you will have unlimited hot water — unless there is a power interruption, in which case, if you are in the shower, your nice, warm shower will suddenly turn icy cold. If that’s no problem for you, then maybe a tankless water heater would be the way to go. In any case, whether you have a standard water heater or a tankless water heater, it’s wise to use hot water frugally. That’s not only a savings in your cost of electricity, but is better for the environment.

  170. Eileen Bowman

    I wash all my clothes in cold water.

  171. JustMe

    I totally agree with what Mr. Muccio, and I am glad He was totally honest about it. As someone who worked in the home improvement industry for over 13 years and in one of the big box stores, I had that question posed to Me many times. I gave the same answer as You and also I would like to add, that I was told by someone who works in the manufacturing of these tankless water heaters, that it will take, upon average, about 10 to 15 years to get back the cost of the product plus installation. Just an extra tidbit =)


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