About Thermoflo

Thermoflo is an established name in the HVAC industry, with a long history of delivering reliable heating and air conditioning products for residential and light commercial applications. We are part of Williamson-Thermoflo®, a company known for product integrity and dependability.

Our product line includes energy-efficient oil- and gas-fired cast iron boilers, oil and gas furnaces, indirect-fired water heaters, air conditioning systems and air handlers.

Thermoflo products are sold through authorized plumbing, heating and HVAC distributors. Service is available through licensed plumbers, professional HVAC contractors, oil dealers and installers.

The Thermoflo® Story

The Thermoflo brand originated in 1946 when a Milwaukee, Wisconsin businessperson and his family formed the Metzger Machine and Engineering Company.

Among the company’s key products were oil furnaces marketed under the trade name Milwaukee Thermoflo. Thermoflo heating equipment quickly gained a reputation for quality and dependability in the HVAC industry.

In 1992, Metzger Machine acquired the assets of The Williamson Company, a Cincinnati, Ohio-based heating and air conditioning manufacturer that had started in the late 1800s. With the operations merged, the Williamson product line joined the Thermoflo brand in Milwaukee.

A New Beginning

In December 1999 another well-established heating equipment company, The Marley-Wylain Company, acquired the brand names Williamson and Thermoflo, from Metzger.

Today, Williamson-Thermoflo operates as an independent business unit of The Marley-Wylain Company.