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Buderus G115WS vs G125BE vs GB125BE

vilord Member Posts: 48
I see that the G125BE was discontinued for the US market, and the GB125BE only made it here for a very short time before being discontinued.

Are they good boilers? There's a distributor near me that has a few still on pallets

GB125 has an AFUE of almost 92, though it is condensing which might not be good for our sulfery #2.
G125 has an AFUE of 90+, whereas the G115WS seems to be around 87.
How much of a difference would we notice between 87 and 90?

(House is 3500SF with lots of windows and cathedral ceilings. Currently has a 191k burnham v7 that's been short cycling since installed, was only rated for 81 AFUE, and has been leaking since last year so the techs won't tune it anymore)


  • Ironman
    Ironman Member Posts: 7,373
    Those boilers can only be sold to someone who has been through training and certification on them and they require special instruments to set them up. I'm not talking about an ordinary oil tech and his instruments, I'm talking about Buderus' tool kit for that boiler. Without the training and tools, the boiler will poison your house with co2.

    Whoever is wanting to sell that boiler directly to you is violating Buderus' requirements and putting you and your family at great risk!

    That's no ordinary oil burner.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • vilord
    vilord Member Posts: 48
    I know it isn't an ordinary boiler, and I would be seeking out a professional in the Massachusetts metro-west area who has been through the proper training and has the proper tools to do the installation, apologies for not being clear about that.

    I'm interested more in the merits of the boilers themselves.
  • vilord
    vilord Member Posts: 48
    Perhaps *that* is the merit of these boilers though... the burners are complicated enough that when it breaks, i won't be able to find someone to fix it.
    Perhaps a G115WS with a Riello is a more sound investment, even if it costs an extra 50 bucks a month for the oil consumption
  • Grallert
    Grallert Member Posts: 644
    The G115WS with a riello is a great boiler, bullet proof.The 125s are the same casting as the 115 though one has a stainless exchanger on the back. The condensing boiler had some issues. The issues I've run into were related to the flue gas over heat switch but that was it really. I really like the burners though. I think Bosch did a poor job of controlling the distribution of these boilers leading to some iffy installations. Now the few that are out there are likely to be a nightmare for the poor tech in the middle of the night.
    Miss Hall's School service mechanic, greenhouse manager,teacher and dog walker
  • GW
    GW Member Posts: 4,691
    we run a G125 at our shop when we have excess oil. I am a fan of the technology, but like mentioned, you need a guy that has a clue. Be mindful that buying your own boiler may have some ill consequences. Most competent heating guys are busy keeping their A list customers happy.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    HVACNUT Member Posts: 5,828
    The BE is a phenomenal burner.
    Like @Ironman said, you had to be Buderus certified to purchase or service that system. If you find someone, he or she should have a laminated card or certificate of training from Buderus for the BE.
    I would go non condensing. It's a lot of extra trouble for 2%.

    I however, am certified. Does your supplier have a G125BE/3? I'm do for a new system before I finish the basement. I met with a Bosch/Buderus rep a couple weeks ago and he didn't know if any were still available.
    I asked Santa for one but he said no because it needs a 5" chimney liner.
  • vilord
    vilord Member Posts: 48
    I forwarded you the supplier info in a direct message.

    Are you near me? Want to price out installing a system? :)
    HVACNUT Member Posts: 5,828
    I answered on your page.
  • spaton66
    spaton66 Member Posts: 2

    I know this is an old discussion, but I am looking for qualified technician in Metrowest area of MA that can service my Buderus G125BE boiler. Installed in 2011 and still running fine but running out of people who can service it. Like to get someone on board before I have a problem.
    HVACNUT Member Posts: 5,828
    edited January 19
    Have you contacted Bosch/Buderus? You needed to be certified to install and service them. 

    The 2107 is trouble for a lot of people as well. 

    Are you willing to pay someone to read the BE burner manual? Because it's a must.

    Combustion is set by adjusting pump pressure to cross the burners inlet air temperature with CO2, so a combustion analyzer is a must. Should be regardless, but...

  • spaton66
    spaton66 Member Posts: 2
    HVACNUT - I contacted Bosch and got the following response, “ Thank you for your request. Unfortunately, our service provider list is temporarily undergoing major changes, and is unavailable until further notice. We kindly like to remind everyone that as long as the contractor is licensed, and they have any questions, they may call our tech support while on site from Monday-Friday, 9AM-5PM (ET), and our tech support is free. We apologize for any inconvenience.” Beginning to wonder if I need to consider swapping out the burner for a simpler one that anyone can work one. It would be too bad because it has been working wonderfully for 12 years now.
    HVACNUT Member Posts: 5,828
    spaton66 said: Beginning to wonder if I need to consider swapping out the burner for a simpler one that anyone can work one. It would be too bad because it has been working wonderfully for 12 years now.
    They're awesome burners. It's a shame the BE didn't last in the States. It was $$ more for only a 4% gain in efficiency over a G115 with a standard burner and I guess most didn't like, or understand the ROI. 

    It's a G115 block. It can be converted to use a Riello BF-3 or BF-5, depending on the size of your boiler.
    I know it works because a guy I used to work with broke the porcelain air tube on one and he installed a Riello temporarily. 

    The BF Riello can be direct vented. A concentric kit can be installed for combustion air.

    You will still need someone who knows oil, and has the instruments to setup and tune it properly. Baffles will likely have to be removed or repositioned to raise the flue gas temperature. How much will depend on what the analyzer says. 
  • jesmed1
    jesmed1 Member Posts: 560
    Does the Buderus G115WS work well with Beckett AFG burners? If one of our existing oversized Weil McLain boilers conks out, I'd like to keep the Beckett AFG burner and downsize, possibly to a G115WS/3. I believe that is an approved burner for the Buderus, but it seems different pros have different preferences.