Weil-McLain introduces B100 compatibility for residential oil boilers
- Weil-McLain
- Sep 18
- 3 min read

Illinois-based Weil-McLain® announced Sept. 17 that its Ultra® Oil, WGO, WTGO and SGO residential oil boilers are now certified for use with biodiesel blends up to 100 percent (B100).
This achievement has been made possible through collaboration with industry leaders R.W. Beckett and Carlin Combustion, as Weil-McLain validates the adaptability of its burners to the elevated blend of biofuel when combined with its popular oil-fired boiler product lines.
Weil-McLain said this advancement underscores its commitment to delivering sustainable heating options and driving environmental progress in the industry.
“Weil-McLain boilers that are B100-certified are designed to operate on this blend of biodiesel fuel with the approved Beckett and Carlin burners,” said Mike Boyd, product manager with Weil-McLain. “These compatible burners have seals and components designed to optimize operation when using biodiesel.”
Using B100 with a certified oil boiler can help reduce greenhouse-gas emissions because biodiesel is a cleaner-burning fuel than petroleum diesel that can provide similar performance while significantly limiting how much carbon dioxide is released into the air.
Other benefits of using a B100-certified boiler include:
Renewable energy source: Biodiesel is made from renewable sources, meaning it can be continually produced by a steady supply of raw materials. By utilizing B100, the dependence on finite fossil-fuel resources can be reduced.
Energy security: Incorporating biodiesel into a fuel mix diversifies energy sources and reduces dependence on foreign oils and petroleum. This can contribute to enhancing energy security and reducing vulnerability to supply disruptions.
Government incentives: In some regions, there may be government incentives, grants or tax credits available for using biodiesel.
“Our new B100-certified boilers mark an important milestone in our commitment to a sustainable future,” Boyd added. “By embracing biodiesel technology, we are not only reducing carbon emissions and environmental impact but also paving the way for a more resilient and renewable energy landscape. This exciting development highlights our dedication to innovation and positions us as a leader in providing energy-efficient solutions that shape the future of heating while making a positive impact on the planet.”
In addition to these benefits, homeowners interested in upgrading to one of these units can reap the rewards of a federal tax credit.
Weil-McLain is a qualified manufacturer (QM) and its residential oil water boilers with an 87 percent AFUE rating installed between Jan. 1, 2025, and Dec. 31, 2025, can be claimed for up to $600 after meeting federal requirements.
Eligible homeowners must include the four-digit QM code of “46H2” when completing their taxes for 2025 using tax form IRS Form 5695, Residential Energy Credits (the QM code may be used in lieu of a product identification number or PIN).
This tax credit can also be used in conjunction with any local Energy Star® rebate programs.
Weil-McLain said its oil-fired boilers are an ideal solution for residential applications.
Available for both water and steam systems, these high-efficiency units are rugged and reliable, the company stated.
And with AFUE ratings of 85 percent to 87 percent, they all can significantly reduce energy waste while providing fuel-cost savings.
The Ultra Oil is the industry’s premium “commercial-grade” residential boiler featuring an easy-to-clean, three-pass heat exchanger.
“The WTGO is the perfect boiler for customers seeking an all-in-one space and domestic hot-water heating appliance, while the SGO (steam) and WGO (water) are great for easy inspection and service due to their quick-open tops and swing-away burner doors that provide full chamber access,” Weil-McLain stated.


































