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Burnham ES2

antman Member Posts: 182
Just wondering if anyone has had the opportunity to install one of these yet.

I had mine!

I needed to do a replacement for my aunt and after going to a presentation on this boiler back in July i was somewhat impressed by it's simplicity and updated features (compared to series2) and i liked the fact it would qualify for a local $500 rebate by the utility company

So i get the boiler downstairs through the bilco doors uncrate it and what do I see, a bright orange tag taped to the draft hood. "this boiler must not be vented into a masonry chimney" Nice! so much for the "Ideal Replacement for Millions of Existing Boiler Installations" because where i live 98% of chimneys are masonry.

My supplier said they were unaware of the situation, oh well who do you blame, myself for not doing all my homework.

Good thing it was for my aunt who understood, otherwise this boiler job would have been for free.

Won't happen again, next time the boiler will be a different shade of blue.


  • TJ_5
    TJ_5 Member Posts: 71

    Have not installed this one yet, but any idea why..
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    It's because...

    it's 85% efficient, meaning it is a near condensing boiler, which means there is a really good chance of the chimney condensing. Masonry chimney's and condensate = disaster.


    There was an error rendering this rich post.

  • JohnNY
    JohnNY Member Posts: 3,230
    edited September 2009
    So you won't be using a Burnham product again because...

    ...why? They want you to use a chimney liner?New flash: Everyone kinda does!

    The directive to use a liner with the ES2 came after the boiler had been in use in the field for a few months. It's not always necessary, but as a precaution, they're presenting it that way.

    It's a good boiler.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • Tim McElwain
    Tim McElwain Member Posts: 4,625
    No gas boiler or furnace

    made today should be installed into an unlined chimney. Due to the lower stack temps the possibility of condensation with its very high acidic content is always there.
  • antman
    antman Member Posts: 182

    Thanks for the news flash John.

    I was just a little put back by the lack of an important issue that was not discussed during the presentation of a new product, as well as by my supplier.I didn't say i wasn't going to use Burnham products again, maybe i would have chosen a different option, such as a sealed combustion boiler and abandoned the chimney altogether.

    I understand liners are an important issue when it comes to some situations but i can't put a chimney liner on every boiler proposal i present.

    Yes it is a nice boiler under certain situations.

    Sorry you misunderstood
  • JohnNY
    JohnNY Member Posts: 3,230
    Got it...

    ...sorry for the smartass tone.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • Mike Kusiak_2
    Mike Kusiak_2 Member Posts: 604
    Low return temps?

    I did some reading in the ES2 literature and I/O manual, and am curious as to how they can allow 100 F return temps with this boiler. From the parts diagram, the cast iron HX looks very similar to a standard series 2 HX. How does Burnham prevent condensing on the exchanger at 100 F, or do they have control software set up to run the

    HX  temp up to above the condensing limit during a firing cycle to dry it off? Are they using some special corrosion resistant cast iron alloy?

    I have seen series 2 boilers run for years at low return temps without obvious rusting, but this is the first time I have seen the manufacturer actually recommend such operation.
  • Old school
    Old school Member Posts: 1
    Chimney Liner for ES2

    Read your post about chimney liner, In Minneapolis, it is standard procedure to line masonry chimneys unless dealing with large 450,000 plus BTU, I am of the opinion that in all cold climates, ST. Louis and above, a liner should be installed unless converting to 90% plus and abandoning the chimney. I have two ES23 boiler in hybrid systems, cast iron and radiant, they seem to work well, but only time will tell.
  • Nwarren
    Nwarren Member Posts: 2
    Low temps in ES2 boiler


    The ES2 has the ability to operate at low return water temps because of the casting design. There are no extra controls, software, valves, piping, or pumps required for the boiler operate with constant 110F return water temps as long as the supply water temp is 130F or greater. ES2 castings incorporate a sophisticated baffle design that evenly distributes return water throughout the each casting. This prevents the return water from collecting in one area of the casting, and creating a cool spot that could condense. The baffling acts like a sparge tube – by evenly distributing water throughout the casting rather than dumping it all in the same spot.

     In addition, the inside surfaces of the water jackets have a special texture which creates turbulence and causes the water to constantly tumble – mixing and blending water temperatures throughout the casting. As water tumbles through the casting, cooler water makes contact with the hotter flue surfaces, enhancing heat transfer, and blending water temps. (Remember - heat transfer is increases when there is a greater temperature differential.)

    The ES2 extracts more heat from the combustion process, which allows the boiler to achieve a higher efficiency (85% AFUE), but this also results in lower flue temperatures than boilers with lower efficiency ratings. The chimney liner requirement is there to protect the homeowner and the installer from chimney or draft problems.  NFPA requires chimney liners in many atmospheric boiler installations, so the liner requirement is not exclusive the ES2 in many instances. Hope this helps.

    Nate Warren

    Product Manager

    U.S. Boiler Co / Burnham
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,526
    Thanks, Nate.

    Nice to see you here!
    Retired and loving it.
This discussion has been closed.