Watts Water Technologies MM431-1 Thermostatic Mixing Valve

Description:

The Watts Powers MM431-1 431 Master Mixing Valve is a standard-temperature thermostatic mixing valve designed to blend hot and cold water to deliver a controlled tempered water supply in commercial and institutional hot water distribution systems. Utilizing advanced thermal actuation technology, it maintains a stable outlet temperature while compensating for changes in inlet pressure and temperature. Commonly installed near boilers, water heaters, and central hot water plants, it is used in hospitals, schools, hotels, apartment buildings, and other facilities requiring centralized temperature control.

Applications:

The MM431-1 is widely used in domestic hot water systems, commercial plumbing installations, institutional buildings, healthcare facilities, hospitality venues, educational campuses, and industrial process water systems. Installed at the hot water source, it provides tempered water for distribution throughout the building while reducing the risk of scalding and improving energy efficiency. The valve is designed for master mixing applications and should be used in conjunction with point-of-use temperature control devices where required by code.

Technical Specifications:

• Manufacturer Part Number (MPN): MM431-1
• Brand: Watts Powers
• Product Type: Master Thermostatic Mixing Valve
• Series: 431 / MM430 Series
• Nominal Valve Size: 3/4 in.
• Inlet Connection: 3/4 in. NPT
• Outlet Connection: 3/4 in. NPT
• Body Material: Rough Bronze
• Temperature Adjustment Range: 90°F to 160°F (32°C to 71°C)
• Hot Water Inlet Temperature Range: 120°F to 180°F (49°C to 82°C)
• Cold Water Inlet Temperature Range: 40°F to 80°F (4°C to 27°C)
• Maximum Operating Pressure: 125 PSI
• Maximum Hot Water Temperature: 200°F (93°C)
• Minimum ASSE 1017 Flow: 3 GPM
• Flow Capacity: Up to 42 GPM at 45 PSI pressure drop
• Flow Coefficient (Cv): 6.32
• Valve Type: Thermostatic Master Mixing Valve
• Compliance: ASSE 1017, CSA B125
• Application: Centralized Domestic Hot Water Tempering Systems

Common Replacements:

• Watts Powers LFMM431-1 
• Watts Powers MM431-2 
• Watts Powers MM431-3