Parsing the Quality of Leonard Mixing Valves

Parsing the Quality of Leonard Mixing Valves

Mar 21st 2024

Even for a plumbing company, Leonard Valve Company has an illustrious history that spans over 110 years. Since 1911, Leonard Valve Company’s plumbing fixtures and parts have been made in America. They are also assembled and tested by hand, right here in the United States.

What’s more, Leonard Valve Company actually provided the world with the first thermostatic mixing valve. It’s quite an interesting story, but in short the founder, Frederick Leonard, scalded his face with untempered water during a hot-towel shave at a local barber shop. That experience culminated in him pioneering, and producing, the world’s first TMV.

Fast forward, and today Leonard Valve Company produces a wide range of valves, including but not limited to thermostatic mixing valves, individual shower valves, emergency mixing valves and wash stations, and even dialysis stations.

You could expect a lot from the company that effectively changed the world of hot water tempering forever. You might as well. Leonard mixing valves feature some of the best technology in the industry. Here are some qualities and traits offered by their fixtures and parts.

Leonard Mixing Valves by Feature and Technology

Leonard thermostatic mixing valves offer any combination of the following features and technology, depending on the model.

  • Thermostatic control: Thermostatic controls are of the utmost importance to public safety in institutional, industrial and commercial settings just as they are in residential settings. They allow holding tanks to be maintained at a temperature high enough to prevent the growth of dangerous pathogens like Legionella and temper it just before the point of use. Leonard mixing valves, like other TMVs, prevent scalds and ensure user comfort. They are also made with highly-responsive copper encapsulated thermostats that are fast-acting and reliable.
  • Color-coded dials: The use of color-coded dials in select shower fixtures improves confidence and streamlines ease of use, providing a higher overall experience.
  • Extremely durable construction: Leonard mixing valves, like all of their plumbing fixtures and components, are made with either brass, bronze, or stainless steel construction (or a combination thereof). These materials are perfect for use in plumbing applications as they are strong and corrosion-resistant, which streamlines maintenance and helps ensure a longer service life.
  • Automatic shutdown features: Many Leonard mixing valves are made with an automatic shutdown feature that protects users in the event of either hot or cold water loss. This feature drops the flow rate to prevent a powerful spray of all-hot or all-cold water, thereby increasing safety.

                               Lead-free design

  • Lead-free design: Leonard Valve Company’s valves are made according to national standards for low lead production. In response specifically to new low lead laws, Leonard’s Nucleus line of electronic mixing valves is made to the current lead-free definition of “not more than .25% when used with respect to the wetted surfaces of pipes, pipe fittings, plumbing fittings and fixtures.”
  • A wide variety of available accessories: Leonard Valve Company, in addition to producing shower and bath combinations, also sells shower heads, diverter spouts, tub spouts, remodel plates, hand showers, vacuum breakers, on/off valves, thermometers, and even institutional shower heads.
  • Vandal resistant designs: Of particular interest in institutional settings, Leonard Valve Company’s designs frequently sport anti-vandal features which resist intentional attempts to damage them and increase their usable service lifespan.
  • Ligature-resistant designs: The incidence of self-harm in certain behavioral institutions is a persistent threat. Fortunately, many Leonard Valve Company products feature ligature resistant designs that make it difficult to attach restraints or ligatures.

                            Lead-free design

Leonard Mixing Valve Maintenance

Like all plumbing fixtures and parts, Leonard mixing valves benefit from routine maintenance. The company recommends that its mixing valves be serviced by a capable, professional plumber at intervals not greater than 6 to 12 months. At minimum, the company recommends that a plumber clean the valve, replace affected or worn parts, and inspect the limit stop.

In their own words, “do not simply install this valve and then forget it!”


There are also some specific problems associated with some valves for which they offer recommended repairs, replacements, or service.

For instance, if a valve is leaking water between the valve cover and body or under the valve knob, Leonard recommends repairing with a gasket kit as a worn or compromised gasket is likely responsible for the leak.

If an affected valve will not effectively control the temperature after it has been cleaned, a rebuilding kit may be needed as there may be damage so extensive that more complete repairs may be necessary to restore functionality.

If a valve allows hot water to pass into the cold water supply (or cold water to pass into the hot water supply) the check stops may need to be serviced or replaced. You can use a check stop kit for this.

Other than these considerations, general good practices for TMV maintenance still apply to Leonard mixing valves. These include but are not limited to regular inspections and periodic valve lubrication. You should also independently test water output temperature to make sure the valve is working as intended, and periodically inspect and replace o-rings and gaskets, as these will wear and can produce leaks if they are not regularly replaced.

                        Lead-free design

What Else Leonard Valve Company Offers?

In addition to thermostatic mixing valves, Leonard Valve Company also offers:

  • Digital master mixing valves and megatrons
  • Emergency mixing valves
  • Industrial wash down stations
  • Vacuum breakers, hose sprays, and hydrotherapy controls for therapeutic applications
  • Dialysis stations
  • And a wide range of other specialty items and parts

Questions About Leonard Mixing Valves?

With such a wide product catalog, it is easy to get lost in the details. If you have any questions before you buy a replacement part, product, or fixture, feel free to get in touch with us directly and we’d be more than happy to help.

You can also sign up here for an account with us so you can start saving on other genuine commercial plumbing products and parts from industry leading manufacturers including but not limited to Sloan, Acorn, Bradley, Chicago Faucet and Symmons in addition to Leonard Valve Company.