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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: 7,119
    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: 563
    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.
  • GW
    GW Member Posts: 4,605
    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
    [email protected]
    HVACNUT Member Posts: 5,028
    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: 5,028
    I answered on your page.