WATTS® 0559115 LFMMV Thermostatic Mixing Valve, 1/2 in Nominal, Solder End Style, 150 psi Pressure, 0.5 to 20 gpm Flow, Copper Silicon Alloy Body, Domestic

  • Country of Origin: US
  • Domestic/Import: Domestic
  • End Style: Solder
  • Flow Capacity: 0.5 to 20 gpm
  • Manufacturer Name: Watts Water Technologies
  • Media: Hot/Cold Water
  • Nominal Size: 1/2 in
  • Pressure Rating: 150 psi
  • Series: LFMMV, LFMMVM1-US
  • Softgoods Material: Buna-N®/EPDM O-Ring
Series LFMMV Thermostatic Mixing Valves maintain and limit mixed hot water to a desired, selectable temperature. The LFMMV series can be set to any temperature between 80 deg F and 120 deg F with flow rates as low as 0.5 gpm and as high as 12 gpm (refer to capacity chart on back). This mixing valve series is listed under ASSE 1017 for valves used in hot water source applications, ASSE 1069 for single-pipe, tempered water applications and ASSE 1070 for valves used in individual or multiple fixture applications and also listed IAPMO cUPC. The LFMMVs feature Lead Free construction to comply with Lead Free installation requirements. The LFMMV-M1 uses a double throttling design to control both the hot and cold water supply to the mixed outlet. The superior flow characteristics of this valve provide accurate temperature control (+/-3 deg F) with low pressure drop across the rated flow range. As an added feature, the LFMMV-M1 series incorporates integral inlet filter washers and check valves in both the hot and cold water inlets to protect against cross flow. The LFMMV-M1 is available with either union thread (-UT), union solder (-US), CPVC (-CPVC ) Quick-Connect (-QC) or PEX (-PEX) end connectors. Maximum Pressure: 150psi (10.55 bar).
  • Features and More


  • Thermal actuation technology for precise temperature control
  • Locking mechanism secures temperature setting
  • Lead free cast copper silicon alloy body construction
  • Solid wax hydraulic principle thermostat assures dependable mixing of hot and cold water
  • Thermostat controls both hot and cold water
  • Solder, threaded, PEX or CPVC, quick connect end connection or with press
  • Adjustment cap with locking feature
  • Integral filter washers and check valves
  • 0.5 gpm at 0.8 psi minimum, 20 gpm at 125 psi maximum
  • 30 psi (207 kPa) minimum supply pressure static
  • 120 to 180 deg F (49 to 82 deg C) hot/ 39 to 85 deg F (4 to 29 deg C) cold inlet temperature
  • Hot water inlet to outlet differential temperature: 5 deg F (3 deg C) above set point
  • Field range: 80 to 120 deg F (27 to 49 deg C) adjustable
  • Accurate within +/- 3 deg F (1.7 deg C)
  • Maximum pressure differential between hot and cold water supplies: 25%
  • The wetted surface of this product contacted by consumable water contains less than 0.25% of lead by weight


  • Commercial
  • Residential and Institutional


  • ASSE 1017/1069/1070 Listed
  • IAPMO cUPC Listed
  • PROP65: This product can expose you to chemicals including lead which is known to the State of California to cause cancer and birth defects or other reproductive harm.


  • 1 year Limited