Watts 0556016 3/4 IN Lead Free Brass Automatic Reseating T and P Relief Valve, 150 psi, 210 degree F, Test Lever, 5 IN Extension Thermostat

Yes. The LF40L valve has a 3/4 inch male NPT inlet that threads into the heater tapping, and a 3/4 inch female NPT outlet for the discharge tube. Standard 3/4 inch T&P prep on residential and commercial storage heaters takes it directly.

The 0556016 uses a 5 inch extension copper thermostat, which is meant for heaters where the tapping sits in a thick jacket or insulation and the probe has to reach into the stored water. On a tank with a shallow tapping a short-shank valve is the right call instead. Measure from the face of the tapping to where the probe needs to sit before you commit to the extension version.

The LF40L 0556016 is set to relieve at 150 psi and at 210 degrees F. It is an automatic reseating valve, so once pressure or temperature drops back below those points it closes again rather than staying open.

The relief setting has to be at or below the working pressure rating of the water heater it protects. This one is factory set at 150 psi, which is the common setting for tanks rated 150 psi. The LF40L family covers 75 to 150 psi, so if your heater's data plate shows a lower maximum, order the matching lower setting instead of this one.

Check it against your burner input. The 0556016 is rated 1,437,600 BTU per hour on pressure discharge and 205,000 BTU per hour on temperature discharge. The temperature figure is the one that governs sizing on a water heater, so the heater's input rating must not exceed 205,000 BTU/hr.

The body is lead free bronze, made for potable hot water service on water heaters. That is what lets it go on domestic drinking water systems in jurisdictions enforcing lead free plumbing requirements.

Yes, the 0556016 comes with a manual test lever. For property managers and MRO crews that matters: annual exercising of the T&P lever is standard practice to confirm the valve is not seized, and this one is built for that.

No. The LF40L is a combination temperature and pressure valve built for water heaters, with a 5 inch probe that must sit in the heated water. On a boiler or a cold water line that probe has nothing to sense and the valve is the wrong device. Use a pressure-only relief valve sized for that application.

Country of origin on the 0556016 is the United States, which matters on public and institutional jobs carrying domestic sourcing requirements.