Watts 40XL-150210 1 1 IN Bronze Automatic Reseating T and P Relief Valve, 150 psi, 210 degree F, Test Lever, 5 IN Ext Thermostat

The copper thermostat probe measures 5 inches, which is the extended-length version used where the valve mounts through thick insulation or on a tank whose tapping sits well outside the water. The probe has to reach into the heated water to sense temperature, so measure from the face of your tapping to the tank wall before ordering. If your opening is shallow, a short-shank T and P is the better match.

No. The 40XL-150210 is not lead free, so it should not go on a potable water system in jurisdictions enforcing the lead free requirement for drinking water components. Use it on non-potable or heating applications, and specify a lead free T and P valve for potable domestic hot water.

Relief capacity is 2,135,000 BTU per hour on pressure and 500,000 BTU per hour on temperature. The temperature figure is the one that governs on a water heater: the valve has to be rated at or above the input rating of the appliance it protects, so a heater firing above 500,000 BTU per hour needs a larger valve.

Both. It's a combination temperature and pressure valve, so it dumps on either an overpressure condition at 150 psi or an over-temperature condition at 210 degrees F. A straight pressure-only relief valve won't protect against a runaway thermostat, which is why code calls for a T and P on storage water heaters.

The 40XL is an automatic reseating design, so once the temperature or pressure drops back below the set point the valve closes again on its own. The test lever lets maintenance staff exercise it on a schedule, which is what keeps the seat from sticking on a valve that rarely operates. Repeated discharge is a sign of a system problem, not a valve fault.

Bronze body, and it's Buy American Act compliant with USA origin, which matters on federal, military, and many state or municipal jobs where domestic-source hardware is written into the spec. Bronze holds up in hot water service better than a plated ferrous body.

The 40L series covers a 75 to 150 psi pressure range, and this particular model, 40XL-150210 1, is factory set at the top of that band at 150 psi with a 210 degree F temperature element. If your system needs a lower set point, you order a different set-pressure model from the series rather than adjusting this one.