Watts LF70A 3/4 3/4 In Brass Lead Free Hot Water Extender Mixing Valve

All three ports on the LF70A 3/4 are 3/4 inch socket connections: hot inlet, cold inlet, and mixed outlet. Socket means the pipe slips into the fitting rather than threading in, so plan on sweat/solder copper stubs at all three ports. If your piping is threaded, you'll need adapters at each connection.

The LF70A adjusts over a 120 to 160 degree F range. It ships without a locked factory setting, so the installer dials in the outlet temperature on site. Because it's an adjustable extender valve rather than a fixed point-of-use device, it's normally set at the water heater to blend a high storage temperature down to a safer delivery temperature.

Hot inlet water needs to be between 120 and 160 degrees F and cold inlet between 40 and 85 degrees F. There also has to be at least a 5 degree F difference between the hot inlet and your desired outlet temperature. If your tank is running below the setpoint plus 5 degrees, the valve can't blend and you'll just get tank temperature at the fixture.

No. The LF70A is a hot water extender, meant to be piped at the water heater outlet to blend stored hot water down before it goes out to the building. It has no cold water bypass and isn't a thermostatic point-of-use device. For scald protection at an individual fixture, use a dedicated point-of-use tempering valve rather than this one.

That's exactly what an extender valve is for. You store water hotter in the tank (the valve accepts hot inlet up to 160 degrees F) and blend it back down at the outlet to a setting between 120 and 160 degrees F, which stretches the usable volume of a given tank. Keep the outlet setpoint at least 5 degrees below the tank temperature or the valve has nothing to blend against.

Minimum static pressure is 30 psi, and the pressure difference between the hot and cold supplies should stay within 25 percent. On a well system or a building with a pressure-reducing valve, check pressure at the heater before you install it. Unbalanced hot and cold pressure is the usual cause of outlet temperature drifting after a correct setup.

It's a lead free brass valve, which is what a plumbing inspector will look for on any potable water line under current lead-content rules. The body carries a rough bronze finish, so it's meant for mechanical room or concealed piping, not exposed trim work.

Yes, the LF70A 3/4 is listed as Buy American Act compliant, USA. That's the item spec facilities and public-agency procurement teams usually need to clear before a submittal goes through on federally funded work.

Order it as Watts LF70A 3/4, series LF70A, manufacturer part number 559133. The 3/4 in the model designation is the port size, and all three ports are 3/4 inch, so there is no mixed-size version of this model to confuse it with.