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Buderus, LT135 a few questions

Hello, I own a Buderus indirect water heater Logalux LT135. I have been doing research on maintenance. The tank sits under the boiler. It is my impression that it is meant to last indefinitely, as long as maintenance is performed correctly. I have been having a devil of a time getting local plumbing contractors to realize that this a is not a short lived disposable replaceable water heater. They cannot understand why it is placed below the boiler as far as replacement is concerned. I answer that it is intended to be serviced, not replaced. The manual explains that an Anode tester manufactured by Buderus can be used to check the Magnesium Anode rod without disassembling the unit. I contacted Buderus USA. They seem to know nothing about the tester or how I might get one. I am surprised that so little is understood about this product. Can anybody offer some insight? Specifically, how I might obtain this tester or an alternative? Thanks so much for your time.


  • omixochitlomixochitl Member Posts: 6
    Can one use any Multimeter to perform the Anode diagnosis? Have any of you used this method?
  • Bob Bona_4Bob Bona_4 Member Posts: 2,083
    edited September 2015
    Barring some breach in the tank lining or a failure in the boiler coil, they are a long term tank. Anode can be checked with a simple multimeter, set to milliamps. .3 to 10 ma is the range that's good, with rod submerged as usual.

    There's always changing it out every few years as recommended, at least once to get a baseline as to how aggressive your water is. Replace when it's diameter is approaching 1/2- 3/4". Note the ma with a new rod for that baseline as well.

    Commendable that this is a thought - most ppl are oblivious!
  • omixochitlomixochitl Member Posts: 6
    Thanks, Bob! Yes, I think that my plumber (he is new to working with me) thinks that I am a strange customer, so many questions! Anyway I am going to buy the multimeter and test it myself. If I get a bad reading, he will open the unit and replace the anode rod. It requires replacing the handhole gasket each time it is opened, which is a pain, but I understand the importance of preventing leaks.
  • Bob Bona_4Bob Bona_4 Member Posts: 2,083
    edited September 2015
    Yw. Of course he will have a new porthole gasket and rod on hand when he goes for it ;)

    My first oil Buderus was about 15 years ago, stacked on a LT200. The learning curve was swift bc I was under the impression the 215 series was "it" and we wrestled that 3 section beast onto the tank only to find out later the 115s existed!

    If he's going to open it up, why not get a new toilet brush and whatever cleaning solution you feel ok with in your potable hot (or none) and swab out the innards including the heating coil? I had one, the public works had done some street work on the main, and stirred up a boatload of mud and sediment, and filmed up the tank.
  • omixochitlomixochitl Member Posts: 6
    Yes, perhaps I should just have it opened up and inspected anyway. It was replaced about 2 years ago after it failed so it's kind of new and I was wondering if I could get by with just the Multimeter test,.
  • omixochitlomixochitl Member Posts: 6
    It failed due to some kind of problem and Buderus replaced it, or so I was told by the plumber at the time. Sometimes I wonder, though as the general opinion is that Bosch wiggles out of any warranty claim.
  • omixochitlomixochitl Member Posts: 6
    Maybe it's still the original tank??? So confusing. Would anybody ever say they replaced the tank and then not actually do it? I had that happen on an auto repair once, I was shocked.
  • Bob Bona_4Bob Bona_4 Member Posts: 2,083
    Anything's possible, it would have been a memorable event due to suspending the boiler during the swap. If it failed once, it'd be hard to believe the one you have now is the same one.
  • Aaron_in_MaineAaron_in_Maine Member Posts: 315
    I had one fail last year. Could not get it warrentied now it is a fancy boiler stand.
    Aaron Hamilton Heating
    [email protected]
    Bob Bona_4
  • Harvey RamerHarvey Ramer Member Posts: 2,215
    I have no experience with them but it sounds like a clumsy, unhandy piece of equipment. The kind I tend to stay away from.

    Still got a bad taste in my mouth for buderous. They sent 2 rads of the wrong model and my supplier ended up eating it. Oh and the rads were sent back so Buderous has the money and the rads and will likely sell them again.

    Ramer Mechanical
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • Paul PolletsPaul Pollets Member Posts: 3,360
    These tanks last 8-10 years. They are a beast to replace and it's why I use stainless indirects. Only Viessmann makes a stainless steel horizontal tank.
  • spoon22spoon22 Member Posts: 32
    These tanks are prone to leaks where the coil leaks and it over pressurized the boiler. Che king the anode is a good start but in my opinion this is a poor design the tank will always leak before the boiler and bosh is tough on their warranties.

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