Announcement

Collapse
No announcement yet.

water heater heat loss

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #46
    Re: water heater heat loss

    Originally posted by JCsPlumbing View Post
    Made me laugh. What's your avy? Looks like a Smiley with a sock in its mouth.

    J.C.

    Yeah....I win the lame avatar award till I get a good one.
    Northern Kentucky Plumbers Twitter Feed | Plumbing Videos

    Comment


    • #47
      Re: water heater heat loss

      I like it though as it makes no sense. Gotta' get my avatar on soon.

      J.C.

      Comment


      • #48
        Re: water heater heat loss

        I'm not sure why I was making things more difficult than they need to be Duck. You are exactly right. The tankless with the higher AFUE will heat water more efficiently. By definition, BTU is the amount of energy it takes to change the temperature of 1 pound of water 1 degree. Plain and simple, the tankless is more efficient at heating water pound for pound. (if the AFUE is the same at all firing rates)

        Andy

        Comment


        • #49
          Re: water heater heat loss

          Originally posted by JCsPlumbing View Post
          Just quickly ran a few numbers. Not checked for accuracy though.

          If a tankless installation costs $1800.00 more to install than a traditional tank model then how would you come out investing that money & annual maintenance costs over 10 years?
          ...
          Originally posted by JCsPlumbing View Post
          $1800.00 invested at 5% for 10 years= $2,968.00 or $24.73/month.

          Your monthly gas bill with a tankless would have to be $24.73 less than with a tank to save anything. Unless I missed something. Anyone tell me if I did as I'm trying to learn & not debate.

          This does not include any maintenance for either.

          J.C.
          How much is your time?

          My whole family of 6 can now shower and bathe in an hour. No way could I do that with my basic 50 gallon natural gas tank prior. 2 or 3 would shower, wait 30 minutes to an hour, then the rest with it cutting it close for the last user both times. Forget about having much hot water after that. Again another 30 minute wait to do laundry or whatever ...

          So again, how much is your time? This would need to be added into your calculations too. If you figure you get paid $25 an hour, so long as a tankless gave you "back" at least an hour of time in that month ... you have made your money back ... closing and basically removing the margin.

          Perhaps a larger tank would have done me good? Maybe one of the fancy direct vented tanks? With that being the case then, now your installation costs go up and you have to refigure things ... closing the margin.

          One of the arguements that the tankless folks use is that they "claim" a tankless lasts twice as a long as a tank. The tankless folks "claim" (have not seen their data) that you would have to replace your tank once and probably twice before the tankless would give out. That would need then to be added into your calculations too ... closing the margin. (You guys are plumbers, so you would know best how true this is.)

          Yes, I just purchased a tankless unit I do not think though that I am trying to justify my purchase. Will I get my money back ... who knows ... I will say though that getting my time "back" has been "priceless".
          Last edited by theoak; 08-27-2008, 12:04 AM.

          Comment


          • #50
            Re: water heater heat loss

            Originally posted by Ruudacguy View Post

            The guy saving $40 a month and only paying 80 cents a therm. Thats 50 therms per month. Almost unbelievable.

            Andy
            That was for two tankless heaters on the same home, not 1 heater. $20 per month per water heater. I think my cost per therm estimate was a liitle low too, probably paying a little over a dollar per therm.
            spodelee

            Until lions have their own storytellers, stories of the hunt shall always glorify the hunter

            Comment


            • #51
              Re: water heater heat loss

              Originally posted by theoak View Post
              How much is your time?

              My whole family of 6 can now shower and bathe in an hour. No way could I do that with my basic 50 gallon natural gas tank prior. 2 or 3 would shower, wait 30 minutes to an hour, then the rest with it cutting it close for the last user both times. Forget about having much hot water after that. Again another 30 minute wait to do laundry or whatever ...

              So again, how much is your time? This would need to be added into your calculations too. If you figure you get paid $25 an hour, so long as a tankless gave you "back" at least an hour of time in that month ... you have made your money back ... closing and basically removing the margin.

              Perhaps a larger tank would have done me good? Maybe one of the fancy direct vented tanks? With that being the case then, now your installation costs go up and you have to refigure things ... closing the margin.

              One of the arguements that the tankless folks use is that they "claim" a tankless lasts twice as a long as a tank. The tankless folks "claim" (have not seen their data) that you would have to replace your tank once and probably twice before the tankless would give out. That would need then to be added into your calculations too ... closing the margin. (You guys are plumbers, so you would know best how true this is.)

              Yes, I just purchased a tankless unit I do not think though that I am trying to justify my purchase. Will I get my money back ... who knows ... I will say though that getting my time "back" has been "priceless".
              Glad your happy with your tankless setup. Happy customer, happy plumber.

              The time factor does not weigh into the equation for me as there are things that can occur with the tankless that can make the customer lose this same amount of time.

              I see alot of traditional tank setups improperly sized giving the impression that a tank setup cannot meet customers needs. I was at one job recently where the house was about 3800 sq.ft., 3 full baths, 4 bedrooms, large cultured marble whirlpool tub.......and only a 50 gal. lowboy electric for H/W.

              A quick answer is yes a good plumber could probably give you your H/W requirements without the 1hr. loss for less than a tankless setup.

              But each customers needs are different to maximize efficiency and investment. I get tired of explaining this to customers and am almost to the point of just installing whatever they want. The onset of the internet, home tv shows, and the home improvement revolution have made alot of smart people think that they are better qualified to analyze what they need/want than a plumber. So I'm close to the point of not offering information and just telling them "You're right."

              The last tankless class I attended the instructor said that the tankless lifespan projections are incorrect and they would not last twice as long. I do not have any current test data on expected lifespan but am constantly gathering information.

              I am not "anti-tankless." Rather, I'm leaning more and more towards recommending them. The prices are dropping. The btus are increasing. The flow rate requirements are decreasing. I'm really interested in the Navien condensing model that's coming. Hope it's the closer answer to what everyone needs.

              I think tankless will take over the market. If they constantly improve with a decreasing price point, then it could be great. Going to be aggravating servicing all of the different models though.

              J.C.

              Comment


              • #52
                Re: water heater heat loss

                Originally posted by JCsPlumbing View Post
                ...
                But each customers needs are different to maximize efficiency and investment. I get tired of explaining this to customers and am almost to the point of just installing whatever they want. The onset of the internet, home tv shows, and the home improvement revolution have made alot of smart people think that they are better qualified to analyze what they need/want than a plumber. So I'm close to the point of not offering information and just telling them "You're right."
                ...
                My intent either is not to say tankless "should" be the only solution out there.

                Each application is unique.

                You stated that not including time was not an option. I similarly could think of examples of "investing" 1800 that would not give a 5% return. Say you used that money to purchase a car ... as soon as you drive the car off the lot, you have lost money and will continue to do so. So I am not sure if your 5% return is necessarily fair either.

                I am half way through the billing cycle and am currently on track for a 20% savings compared to this month last year. School did start almost a week earlier this year and the wife being pregnant is taking a bath at least once a day on top of a shower too, so I may end up just breaking even. Assuming I get the 20%, I used 16 therms last year, so that saves me just over 3 therms or a whole $3 (about). Lets party! Does that give me the $25 according to your calculations (with the 5% return) - no. If you are going to include your investment calculations however, then I get to include my time calculations Therefore, I break even and even come out ahead

                You're right ... tankless is not for everyone. Thus far however, for me, it is "paying off" ...

                Comment


                • #53
                  Re: water heater heat loss

                  Originally posted by theoak View Post
                  My intent either is not to say tankless "should" be the only solution out there.

                  Each application is unique.

                  You stated that not including time was not an option. I similarly could think of examples of "investing" 1800 that would not give a 5% return. Say you used that money to purchase a car ... as soon as you drive the car off the lot, you have lost money and will continue to do so. So I am not sure if your 5% return is necessarily fair either.

                  I am half way through the billing cycle and am currently on track for a 20% savings compared to this month last year. School did start almost a week earlier this year and the wife being pregnant is taking a bath at least once a day on top of a shower too, so I may end up just breaking even. Assuming I get the 20%, I used 16 therms last year, so that saves me just over 3 therms or a whole $3 (about). Lets party! Does that give me the $25 according to your calculations (with the 5% return) - no. If you are going to include your investment calculations however, then I get to include my time calculations Therefore, I break even and even come out ahead

                  You're right ... tankless is not for everyone. Thus far however, for me, it is "paying off" ...
                  Unless you are buying a vehicle for depreciation purposes or an rare classic with rising value, to say a vehicle purchase is an investment is laughable. As far as 5% return not being fair, it's more than fair. I used 5% in my scenario as CONSERVATIVE returns. If you are unable to achieve 5% even in the current Bear Market then you should probably change your strategy.

                  Everyone is not like me and that's one of my faults. I would rather change my behavior towards usage with a tank model to increase bottom line for the longterm. Doesn't make me right. Doesn't make you right. Just another way to look at things, just like the way you feel about it is another way also.

                  J.C.

                  Comment


                  • #54
                    Re: water heater heat loss

                    JC,

                    If you're looking at a tankless for saving money, then I think you're right on with your analysis method. Any investment (deployment of capital) should be compared against other possible uses of that capital.

                    On the other hand, if you want one of these because it will make your life more enjoyable; who cares about the pay back? My table saw doesn't save me any money over buying furniture (probably costs me a bunch more); but it sure is fun.

                    Anyway, both of you have it wrong. You should get an 80 gallon indirect tank like me.

                    Comment


                    • #55
                      Re: water heater heat loss

                      I think we are saying the same thing.

                      What is "right" really depends on the application, and the priorities.

                      I liken it to a garage sale ... someone's garbage is another's treasure.

                      The same thing here applies to tank versus tankless. Each person has their set of priorities. What is deemed important, or a treasure, to one, may be pointless, or garbage, to another.

                      It appears that my "treasure" is your "garbage". In the end though ... we are both happy That is what counts

                      Comment


                      • #56
                        Re: water heater heat loss

                        Right on Charles. (<-right? Memory) Like I said sometimes I've been too cheap and maybe expect others to be. Raised to save to a fault. Working on it.



                        J.C.

                        Comment


                        • #57
                          Re: water heater heat loss

                          J.C. <--- cheap, cheap, cheapity cheap!
                          Water Heater Reviews & Water Heater Information

                          Comment


                          • #58
                            Re: water heater heat loss

                            Originally posted by theoak View Post
                            How much is your time?

                            My whole family of 6 can now shower and bathe in an hour. No way could I do that with my basic 50 gallon natural gas tank prior. 2 or 3 would shower, wait 30 minutes to an hour, then the rest with it cutting it close for the last user both times. Forget about having much hot water after that. Again another 30 minute wait to do laundry or whatever ...

                            So again, how much is your time? This would need to be added into your calculations too. If you figure you get paid $25 an hour, so long as a tankless gave you "back" at least an hour of time in that month ... you have made your money back ... closing and basically removing the margin.

                            Perhaps a larger tank would have done me good? Maybe one of the fancy direct vented tanks? With that being the case then, now your installation costs go up and you have to refigure things ... closing the margin.

                            One of the arguements that the tankless folks use is that they "claim" a tankless lasts twice as a long as a tank. The tankless folks "claim" (have not seen their data) that you would have to replace your tank once and probably twice before the tankless would give out. That would need then to be added into your calculations too ... closing the margin. (You guys are plumbers, so you would know best how true this is.)

                            Yes, I just purchased a tankless unit I do not think though that I am trying to justify my purchase. Will I get my money back ... who knows ... I will say though that getting my time "back" has been "priceless".
                            Well, I suppose the whole family could get in the same shower and be through in 10 minutes. Think of how much time, gas, and water that would save.

                            If you're telling me you have teenagers and they are out of the shower in less than an hour I would have to call you a prevaricator. Especially now that they have "endless" hot water and no dad yelling at them that they're using up all the hot water. (There's alot to be said for depleting the tank types in certain situations.)

                            I would love to hear a report from you about your flow rate when three of you are taking showers (in different bathrooms) and mom is doing the dishes.

                            Have you had this unit during an Idaho winter yet?. What is your incoming water temp?

                            Seriously, how often do all six of you have to take a shower within an hour?
                            "Man will do many things to get himself loved, he will do all things to get himself envied." Mark Twain

                            Comment


                            • #59
                              Re: water heater heat loss

                              The return of the Slim man!

                              Get us another plumbing riddle going soon.

                              J.C.

                              Comment


                              • #60
                                Re: water heater heat loss

                                Originally posted by SlimTim View Post
                                Well, I suppose the whole family could get in the same shower and be through in 10 minutes. Think of how much time, gas, and water that would save.

                                If you're telling me you have teenagers and they are out of the shower in less than an hour I would have to call you a prevaricator. Especially now that they have "endless" hot water and no dad yelling at them that they're using up all the hot water. (There's alot to be said for depleting the tank types in certain situations.)

                                I would love to hear a report from you about your flow rate when three of you are taking showers (in different bathrooms) and mom is doing the dishes.

                                Have you had this unit during an Idaho winter yet?. What is your incoming water temp?

                                Seriously, how often do all six of you have to take a shower within an hour?
                                A family with 4 kids of school age and two working parents often have to compromise by taking showers before bed.

                                Comment

                                Working...
                                X