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  • Re: Navien tankless heaters

    Originally posted by SewerRatz View Post
    Mr Lee, what about the pressure loss of a Navien verses a Noritz Noritz has a 30 PSI loss at a 11 GPM flow, where Navien has a 30 PSI loss at a 3 GPM flow, also Noritz unit has a temperature fluctuation of 3º F +/- and Navien has a 10º F +/- fluctuation. Also Navien claims to have a stainless steel secondary heat exchanger but only part of it is stainless steel where the Noritz is 100 % stainless steel.

    These are some issues I hope they addressed as well as some of the others in their what now 4th generation of tankless water heaters?
    Sorry I don't know the noritz unit well but makes sure to compare their 94% to make it equal. Looks like you may be reading the comparison sheet that Noritz put out and in fact about 8 out of the 11 bullets were misrepresented.

    One of those being the heat exchanger claim. 100% of the waterways is S.S. The secondary heat exchanger housing is aluminum but no water, only condensate comes in contact with that. To be fair then we could say the noritz unit isn't 100% S.S on the 2nd heat exchanger because it is surrounded by sheetetal.

    Comment


    • Re: Navien tankless heaters

      Okiebill

      Navien being a million dollar line for us, I'm somewhat of a fan. Course I like Trane much more at 15m.

      Comment


      • Re: Navien tankless heaters

        Originally posted by Lee H View Post
        Okiebill

        Navien being a million dollar line for us, I'm somewhat of a fan. Course I like Trane much more at 15m.
        I guess it is safe to say that your secondary tankless WH line is not Rinnai or Noritz

        Oh yea, Welcome to the Ridgid Boards

        Comment


        • Re: Navien tankless heaters

          Lee:
          You sound very knowledgeable to me and hope you keep talkin on this forum. I am gonna take my 1st plunge soon on installing a tankless heater. To be quite honest I have avoided them in the past due to all the issues, everyone talks about, and I'm a 1 man show, and can not afford call backs.

          But the main questions I have right now is this, {no technical questions yet, but they are sure to come}.
          You talk about having to add a mixing valve to outlet of heaters, due to temp. fluctuations. This is a new one on me but just adds to the list of issues with these things. Who pays for all the hours spent, & materials used, fine tuning these things? How can you even think about charging the customer for these unexpected add ons? And how do you stay in business if you don't?
          Actually I wouldn't mind hearing from any of you on this.

          Comment


          • Re: Navien tankless heaters

            Originally posted by Don the plumber View Post
            Lee:
            You sound very knowledgeable to me and hope you keep talkin on this forum. I am gonna take my 1st plunge soon on installing a tankless heater. To be quite honest I have avoided them in the past due to all the issues, everyone talks about, and I'm a 1 man show, and can not afford call backs.

            But the main questions I have right now is this, {no technical questions yet, but they are sure to come}.
            You talk about having to add a mixing valve to outlet of heaters, due to temp. fluctuations. This is a new one on me but just adds to the list of issues with these things. Who pays for all the hours spent, & materials used, fine tuning these things? How can you even think about charging the customer for these unexpected add ons? And how do you stay in business if you don't?
            Actually I wouldn't mind hearing from any of you on this.
            I never had to add a tempering valve after a Rinnai , Takagi or a Noritz tankless system I have installed. Unless you look at my commercial installs but that is to temper down the water to a safe temperature for the domestic hot water.
            Ron Hasil Lic #058-160417
            A-Archer Sewer & Plumbing specializing in:
            Tankless Water Heaters | Drain and Sewer Cleaning
            Sump and Ejector Pumps | Backflow RPZ Testing

            Comment


            • Re: Navien tankless heaters

              Originally posted by Don the plumber View Post
              Lee:
              You sound very knowledgeable to me and hope you keep talkin on this forum. I am gonna take my 1st plunge soon on installing a tankless heater. To be quite honest I have avoided them in the past due to all the issues, everyone talks about, and I'm a 1 man show, and can not afford call backs.

              But the main questions I have right now is this, {no technical questions yet, but they are sure to come}.
              You talk about having to add a mixing valve to outlet of heaters, due to temp. fluctuations. This is a new one on me but just adds to the list of issues with these things. Who pays for all the hours spent, & materials used, fine tuning these things? How can you even think about charging the customer for these unexpected add ons? And how do you stay in business if you don't?
              Actually I wouldn't mind hearing from any of you on this.
              Same as you I bet. I do ANYTHING to avoid callbacks. Check, doublecheck, check again. Research etc.

              I seek least problematic & good performance.

              For my area Rinnai would be #1 to meet that criteria.

              A close 2nd would be Rheem/Paloma & Takagi.

              We have zero support or sales locally for Navien or Noritz. I hear good things about Noritz and negative things about Navien that some say they are working out.

              Time will tell & I wish Navien the best but I will not be the test contractor. I'll let others test and watch to make sure they have the units tuned correctly and QC in order straight from the factory.

              By the way, I still have a VERY low adjustment or callback ratio on tank water heaters.

              Good luck.

              J.C.

              Comment


              • Re: Navien tankless heaters

                Originally posted by JCsPlumbing View Post
                Same as you I bet. I do ANYTHING to avoid callbacks. Check, doublecheck, check again. Research etc.

                I seek least problematic & good performance.

                For my area Rinnai would be #1 to meet that criteria.

                A close 2nd would be Rheem/Paloma & Takagi.

                We have zero support or sales locally for Navien or Noritz. I hear good things about Noritz and negative things about Navien that some say they are working out.

                Time will tell & I wish Navien the best but I will not be the test contractor. I'll let others test and watch to make sure they have the units tuned correctly and QC in order straight from the factory.

                By the way, I still have a VERY low adjustment or callback ratio on tank water heaters.

                Good luck.

                J.C.
                You are right J.C., install a standard tank heater, & never have an issue, for the contractor, or the homeowner for the life of the tank. I simply am failing to see any savings on the consumers side, or any big profit on our side. 1 call back and my profit is out the window.
                Not only that, no-one ever talks about the customer not having hot water, while trying to address these problems. My customers would be pissed off, and rightfully so.

                Comment


                • Re: Navien tankless heaters

                  Originally posted by Don the plumber View Post
                  You are right J.C., install a standard tank heater, & never have an issue, for the contractor, or the homeowner for the life of the tank. I simply am failing to see any savings on the consumers side, or any big profit on our side. 1 call back and my profit is out the window.
                  Not only that, no-one ever talks about the customer not having hot water, while trying to address these problems. My customers would be pissed off, and rightfully so.
                  There are many issues involving tankless that have been discussed pretty thoroughly in past threads.

                  Cold water sandwiching.
                  No power, no hot water.
                  Delays.
                  Changing gas services for increased peak demand.
                  Yearly required maintenance.
                  Volume restriction & winter temperature rise.

                  Etc.

                  I have not been very "pro" tankless but am interested in Seweratz commercial successes & satisfied customers. I think that may be something to consider as these situations may be more likely to lend themselves to tankless designs.

                  J.C.

                  Comment


                  • Re: Navien tankless heaters

                    I have the latest pdf troubleshooting guides from the Navien and I could upload them here (or upload them to my server and post a link here ), When I got started with the tankless waterheaters , I called the company and they sent me everything they had (troubleshooting info) ...

                    With the switches on the circuit board you can troubleshoot just about everything ..

                    I original circuit board was a kdc-321-5m v 1.05 and when I called the support people they informed me that some of the units with that version , had wild temperature swings , So they sent me a kdc-321-5m v 2.0 and that they say fixed that issue ..

                    Another thing they recommended was to install a 5 micron filter on the cold water inlet , any iron particles in the water could interfere with the water flow sensor ...

                    Comment


                    • Re: Navien tankless heaters

                      Originally posted by JCsPlumbing View Post
                      There are many issues involving tankless that have been discussed pretty thoroughly in past threads.

                      Cold water sandwiching.
                      No power, no hot water.
                      Delays.
                      Changing gas services for increased peak demand.
                      Yearly required maintenance.
                      Volume restriction & winter temperature rise.

                      Etc.

                      I have not been very "pro" tankless but am interested in Seweratz commercial successes & satisfied customers. I think that may be something to consider as these situations may be more likely to lend themselves to tankless designs.

                      J.C.
                      Lets address your issues you brought up.
                      1. Cold water sandwiching. Cold water sandwich is where the pipes to the fixtures and the water in the heat exchanger cool off, and the time it takes the heater to get to temperature and the water to flow hot at the fixture. This problem is the same with tank heaters, there is a delay to how long the water takes to flow before it gets hot. My apartment takes a good minute for me to get hot water out of the taps and I am only 50 feet from a 120 Gal, 500K water heater. Now this problem is exaggerated when a contractor our home owner opts to move the tankless heater to an outside wall which puts more length on the water pipes which in turn ads more time to get hot water.
                      2. No power, no hot water. Same issue if you have a power vent water heater. Lots of tankless water heaters Rinnai, Noritz and Takagi can run off a battery for a short time. Guess you could use a Sump pro system for the power vents. Most people that have power vent units are the ones that opt to go with a tankless since the cost of the power vent unit is nearly as expansive as a tankless. They also see that once they spend the money on a tankless system that if something goes wrong with the unit they only need to repair the broken or leaking part, no longer need to buy a whole new power vent tank for 2K+
                      3. Delays. See issue #1 the delay is also refereed to as cold water sandwich.
                      4. Changing gas services for increased peak demand. Now some gas services can handle the 199K BTU of a single tankless heater along with the other loads, but others may not. This is something you do have to check to make sure the gas meter can provide enough BTU's for the whole house. Some of the homes where I installed 2 units to deal with peak demand did have to have their gas meter upgraded. On a good point the gas company was more than happy to do it for free.
                      5. Yearly required maintenance. I agree on this. Most people do not drain down their tank heaters or even check the T&P valve like they are supposed to every year. How do we expect them to delime their tankless? Well you can sell them a service contract to come out and delime it yearly for them Also some of the Tankless heaters have an error code for when its time to delime them.
                      6. Volume restriction & winter temperature rise. This is a non-issue as long as you properly size the tankless heater to the cold incoming water. Again in most cases for me with an incoming water temp of around 50º people can get away with a single heater with one bath house. Even a two bath home can get away with a Noritz 931 or a Rinnai R94LSi But when you get 3 or more bathrooms two Rinnai's R75LSi or the Noritz 751 DVC would be a better choice. Also I like putting in two units this way you have redundancy in case one heater needs to be taken out of service for repairs. The home owner will then still have hot water.
                      Ron Hasil Lic #058-160417
                      A-Archer Sewer & Plumbing specializing in:
                      Tankless Water Heaters | Drain and Sewer Cleaning
                      Sump and Ejector Pumps | Backflow RPZ Testing

                      Comment


                      • Re: Navien tankless heaters

                        Originally posted by Total View Post
                        I have the latest pdf troubleshooting guides from the Navien and I could upload them here (or upload them to my server and post a link here ), When I got started with the tankless waterheaters , I called the company and they sent me everything they had (troubleshooting info) ...

                        With the switches on the circuit board you can troubleshoot just about everything ..

                        I original circuit board was a kdc-321-5m v 1.05 and when I called the support people they informed me that some of the units with that version , had wild temperature swings , So they sent me a kdc-321-5m v 2.0 and that they say fixed that issue ..

                        Another thing they recommended was to install a 5 micron filter on the cold water inlet , any iron particles in the water could interfere with the water flow sensor ...
                        Noritz and Rinnai both already have this filter in place. Also I can trouble shoot both said units with out even taking the cover off. Noritz lets me see all the diagnostics from the remote controller. I can see actual flow rates through the heater, I can see servo positions, I can read incoming water temperature and outgoing temperature. And if I or any one that installs these units are not sure about the troubleshooting steps or not confident enough with themselves, they both have great 800 Tech support that will walk you though all the troubleshooting step by step.
                        Ron Hasil Lic #058-160417
                        A-Archer Sewer & Plumbing specializing in:
                        Tankless Water Heaters | Drain and Sewer Cleaning
                        Sump and Ejector Pumps | Backflow RPZ Testing

                        Comment


                        • Re: Navien tankless heaters

                          Originally posted by Lee H View Post
                          Clarifications:
                          Navien is not American made; no Tankless gas unit is for that matter.
                          Rheem is a Paloma unit and it has always been a jap unit.

                          Typically manufacturers are not allowed to post on sites like this because of all the misinformation and bashing. Take a lesson from heatinghelp.com, those guys actually get together on occasion and factory guys are in attendance but they don't post.
                          I was under the impression they were made in California.

                          That said, screw 'em, I'll stiick with Rinnai or Rheem (yeah, Paloma is Rheem, as is Ruud)


                          Originally posted by SewerRatz View Post
                          I was going to ask, when did Navien become a US made unit? Where does it say that? Last I heard it is Korean made, and always has been.
                          My bad, somehow I got the impression Navien was American made when I first heard of it in this forum about 1-1/2 years ago, that's why the unit stuck out in my memory.

                          Originally posted by Lee H View Post
                          Excellent
                          may I sell you a combustion analyzer? Get ready for the future!
                          You've made insinutative comments regarding basic installation equipment that you feel plumbers don't carry, helpfully exposing the wrongs of the trade, I have a cheapie Bacharach like er'yone else does...do I get a cookie?
                          Gold star for my forehead? Am I adequate?


                          Originally posted by Lee H View Post
                          I've been a reader of this forum for quite some time and like a lesson I once learned from another forum once, the same dozen people like to control the boards and bicker back and forth. Yes I'm new to posting and if you don't want me let me know I can leave but doesn't it get a bit boring with the same people?
                          I've also made observations regarding professional/trade forums as well, non members of the profession very frequently enter the forum, pass judgement or dutifully expose the inadequacies of the profession as well as the members of the forum, often offering their "helpful" advice and criticisms on how they can improve their trade.

                          Have you noticed that as well?

                          Comment


                          • Re: Navien tankless heaters

                            All jabs aside, it sounds to me like the trade off for the Navien's efficiency is both flow restriction and temperature fluctuation.

                            If you really break down the difference in 10% efficiency for say s small family of 3 that maybe spends $50 a month for hot water, you might be talking a difference in savings of $5 a month on the water heating portion of the gas bill.

                            This brings one question up, how much are these units?

                            I get Rinnai or Rheem for $1100 for the 7.5 gpm units, the snorkel kits run another $300, which is a perk for the Navien if the base price is reasonable.

                            That ten degree temperature fluctuation, though, is a tough sell.

                            Comment


                            • Re: Navien tankless heaters

                              Originally posted by DuckButter View Post
                              All jabs aside, it sounds to me like the trade off for the Navien's efficiency is both flow restriction and temperature fluctuation.

                              If you really break down the difference in 10% efficiency for say s small family of 3 that maybe spends $50 a month for hot water, you might be talking a difference in savings of $5 a month on the water heating portion of the gas bill.

                              This brings one question up, how much are these units?

                              I get Rinnai or Rheem for $1100 for the 7.5 gpm units, the snorkel kits run another $300, which is a perk for the Navien if the base price is reasonable.

                              That ten degree temperature fluctuation, though, is a tough sell.
                              10 degrees temp variation ? Why then do I not get the massive temperature swings that you are stating , I checked and the temp stays steady at 120 deg F.. Maybe back to the install / gas pressure / gas line size ??

                              Comment


                              • Re: Navien tankless heaters

                                Originally posted by Total View Post
                                10 degrees temp variation ? Why then do I not get the massive temperature swings that you are stating , I checked and the temp stays steady at 120 deg F.. Maybe back to the install / gas pressure / gas line size ??
                                Maybe you got a good one.

                                J.C.

                                Comment

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