For more than 80 years, McDonnell & Miller has been the leader in engineering and manufacturing a comprehensive line of boiler controls, liquid level controls and flow switches for steam and hot water boilers. In 1924, recognizing the need for an improved way to protect low pressure steam heating boilers, Everett Nicholas McDonnell, in collaboration with Pat Miller, formed McDonnell & Miller. Its first products were automatic boiler water feeders for low pressure steam boilers. The company prospered, and during the 1930s it developed many products that are still used today, including a patented cold feed valve, and a quick hook-up fitting that made the valve very easy to install. In the mid 1930s, new boilers with automatic burners created the need for a safety device that would turn off the burner if a low water condition developed. This led to the development of McDonnell & Miller’s low water cut-off product line for hot water and steam boilers. By the end of the decade, code authorities were mandating that pressure boilers be protected with some type of low water sensing device. Continued From Above Pent-up consumer demand after World War II led to updates in automatic heating equipment. McDonnell & Miller reaped the benefits of this demand, and built a new factory in the late 1940s. Manufacturing, though considerably modernized, still takes place in this facility today.McDonnell & Miller built its first flow switch in the 1930s for use in steam locomotives. Sales declined with the passing of the steam locomotive, but in the early 1950s, new market opportunities arose in commercial and industrial air conditioning to prevent a freeze-up of the chiller. Many new flow switch models were added, additional markets developed, and McDonnell & Miller created one of the broadest flow switch lines in the world.
In 1971, McDonnell & Miller was acquired by ITT Industries, Inc. The company, now part of a division that includes Bell & Gossett, Domestic Pump and Hoffman Specialty, continues to expand its line of boiler controls, liquid level controls and flow switches for residential, commercial and industrial applications. The facility received ISO 9001 and ISO 14001 certification as the result of its dedication to designing, producing and marketing the very highest quality products.