Boiler controls, such as liquid level controls, low-water cut-offs, and flow switches from McDonnell & Miller, are now available online.
McDonnell & Miller, a Xylem brand, is a leader in engineering and manufacturing boiler controls for steam and hot water boilers in industrial, commercial, and residential applications.
McDonnell & Miller Low Water Cut-Offs
Low water cut-offs (LWCOs) from McDonnell & Miller hold a boiler's water level at the recommended limit to maintain maximum efficiency. LWCOs are mounted at the boiler water line and start and stop the pump as the boiler water dictates. McDonnell & Miller low water cut-offs are available in several styles, with pump controls if desired, for commercial and industrial low or high-pressure boiler applications.
Read more about McDonnell & Miller LWCOs
McDonnell & Miller Water Feeders
Water feeders from McDonnell & Miller open if a boiler's water line drops to the operating point, typically near the bottom of the gauge glass. The water feeder will then open and add enough water to keep the boiler operating at a safe minimum water level. Once it has added the right amount of water, the water feeder will close.
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McDonnell & Miller Liquid Level Controls
Liquid level controls from McDonnell & Miller should be used with other pneumatic devices for liquid level sensing in a tank or pressure vessel where electrical processes are unsuitable, such as in certain hazardous locations.
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McDonnell & Miller Switches
McDonnell & Miller offers flow switches to control liquid or air in pipes for general purpose and high sensitivity needs, as well as industrial applications.
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McDonnell & Miller Valves
McDonnell & Miller offers several types of valves to supplement the operation of heating systems, such as blowdown valves and test valves.
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McDonnell & Miller Repair Parts
McDonnell & Miller offers a wide range of repair and replacement parts for their products, including probes, castings, paddles, gaskets, and more.
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The History of McDonnell & Miller
For over 95 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 (M&M). 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 to turn off the burner if a low water condition developed. This led to the development of M&M’s low-water cut-off product line for hot water and steam boilers. By the decade’s end, code authorities mandated that pressure boilers be protected with a low water sensing device.
Pent-up consumer demand after World War II led to updates in automatic heating equipment. M&M 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.
M&M built its first flow switch in the 1930s for steam locomotives. Unfortunately, sales declined with the passing of the steam locomotive. Still, in the early 1950s, new market opportunities arose in commercial and industrial air conditioning to prevent a freeze-up of the chiller. As a result, many new flow switch models were added, additional markets were developed, and M&M created one of the broadest flow switch lines in the world.
In 1971, M&M was acquired by ITT Industries, Inc. The facility received ISO 9001 and ISO 14001 certifications due to its dedication to designing, producing, and marketing the highest quality products.
On October 31, 2011, Xylem completed its spinoff from ITT Corporation and began a new chapter as a leading global water technology company with operations in more than 150 countries. Formed from several of ITT’s water and fluid handling and analytics businesses, Xylem brings to the marketplace a passionate, talented, and experienced workforce, well-known industry-leading brands and water solution products, and a shared commitment to making a difference in communities around the world.