
Specifications
Description
The Watts LFMMV-HTK 3/4 is a 3/4" lead-free hot water tank capacity extender kit with Hose connections. It blends hot and cold water to hold a field-adjustable outlet temperature of 80°F to 120°F. It is listed to ASSE 1017, ASSE 1070. It features a copper body and a epdm seat. This model is certified lead-free for potable-water installations.
The LFMMV-HTK hot water tank capacity extender is designed to maximize hot water systems for both performance and safety in residential and commercial applications. This kit enables water heaters to operate at higher temperatures, reducing the risk of Legionella and other harmful bacteria while delivering up to 133 percent more hot water capacity depending on storage and incoming water temperature. Featuring an advanced thermostatic mixing valve, this kit ensures precise temperature control, 80 to120 degrees F, and complies with ASSE 1017 and 1070 standards. This kit includes a 3/4 inch model LLMMV mixing valve, stainless steel connector, tee, and elbow for easy installation.
Features
- Boost hot water capacity, up to 133 percent more usable hot water by running your tank at higher temperatures
- Thermostatic mixing valve for precise temperature control to keep water between 80 to 120 degree F
- Includes valve, stainless steel connector, tee, and elbow for easy installation
- ASSE 1070, ASSE 1017 and UPC listed
- Durable, lead free design built with corrosion-resistant copper silicon alloy for long-lasting reliability
Common Questions
- Can I use this at a lavatory — is it ASSE 1070 listed?
- Yes. This valve is listed to ASSE 1070, the standard for point-of-use scald protection, so it is legal to install it serving a lavatory, sink or similar fixture. Because it additionally carries ASSE 1017, the same valve may be used at the water heater as a point-of-distribution tempering valve. Its outlet adjusts from 80°F to 120°F. Note ASSE 1070 does not cover showers — an in-shower device must be ASSE 1016 listed.
- What temperature range does it deliver?
- The outlet temperature is field-adjustable from 80°F to 120°F. It holds that setting down to 0.5 gpm of flow.
- Does it have integral checks?
- Yes. Check valves are built into the hot and cold inlets to stop cross-flow between the supplies, along with integral filter washers/screens that keep debris off the thermostat. No separate check valves are needed at the valve.
- Can I lock the temperature setting?
- Yes. A locking mechanism secures the temperature setting once it is dialed in, so it cannot be moved without deliberately unlocking it.
Specifications
- Type: Mixing/Tempering
- Size: 3/4"
- Connection: Hose
- Body Material: Copper
- Seat / Seal Material: EPDM
- Country of Origin: United States
- Warranty: 1 Year Limited
- MPN: LFMMV-HTK 3/4
- Certifications: ASSE-1017, ASSE-1070, IAPMO
- Lead-Free: Yes
- ASSE Listing: ASSE 1017;ASSE 1070
- Install Point: Point of Distribution
- Outlet Temp — Min (°F): 80
- Outlet Temp — Max (°F): 120
- Minimum Controllable Flow (gpm): 0.5
- Integral Checks & Filter Washers: Yes
- Locking Temperature Adjustment: Yes
- Temperature Gauge Included: No
- Applications: Water Heater
Product Information
Dimensions
| Size Nominal | 3/4" | End Connection | Hose |
Details
| Series | LFMMV | Device Type | Mixing/Tempering |
| Lead Free | Yes | Body Material | Copper |
| Seat Material | EPDM | ASSE Listing | ASSE 1017, ASSE 1070 |
| Install Point | Point of Distribution | Outlet Temp Min °F | 80.0 °F |
| Outlet Temp Max °F | 120.0 °F | Flow Min GPM | 0.5 GPM |
| Integral Checks | Yes | Locking Adjustment | Yes |
| Applications | Water Heater | — | — |
Certifications & Standards
| ASSE-1017 | ASSE-1070 |
| IAPMO | — |
Compare with similar products

| ASSE Listing | ASSE 1017, ASSE 1070
| ASSE 1017
| ASSE 1017
|
| Install Point | Point of Distribution
| Point of Distribution
| Point of Distribution
|
| Outlet Temp Min °F | 80.0 °F | 90.0 °F | 90.0 °F |
| Outlet Temp Max °F | 120.0 °F | 160.0 °F | 160.0 °F |
| Flow Min GPM | 0.5 GPM | 0.5 GPM | 0.5 GPM |
| Integral Checks | Yes | Yes | Yes |
| Locking Adjustment | Yes | Yes | Yes |
| Cold Failure Shutoff | — | Yes | Yes |
| Inlet Hot Max °F | — | 200.0 °F | 200.0 °F |
| Union Connections | — | Yes | Yes |
| Applications | Water Heater
| Water Heater, Tankless / Boiler, Radiant Heat, Whole House
| Water Heater, Tankless / Boiler, Radiant Heat, Whole House
|
| Series | LFMMV
| LF1170
| LF1170
|
| Country Of Origin | United States
| United States
| United States
|
| Warranty | 1 Year Limited
| 1 Year Limited
| 1 Year Limited
|
| Spec Sheet | |||
| Install Sheet | |||
| Device Type | Mixing/Tempering
| Mixing/Tempering
| Mixing/Tempering
|
| Size Nominal | 3/4"
| 1/2"
| 3/4"
|
| Lead Free | Yes | Yes | Yes |
| End Connection | Hose
| NPT
| PEX
|
| Body Material | Copper
| Copper
| Copper
|
| Seat Material | EPDM
| EPDM
| EPDM
|
| Max Pressure PSI | — | 150.0 psi | 150.0 psi |
| Certifications | ASSE-1017, ASSE-1070, IAPMO
| ASSE-1017, IAPMO
| ASSE-1017, IAPMO
|
| Pack Qty | — | 12
| 12
|
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