Abstract: An air valve includes a valve body and a disc configured to engage a seat. An inlet port is upstream from the seat, and an outlet port is downstream from the seat. A stern is connected to the disc, and a piston is connected to the stern, wherein the piston has first and second positions. A chamber is defined at least in part by the piston and the valve body. A clearance between the valve body and the stem has a first cross-sectional area. One or more relief ports provide fluid communication from the chamber through the valve body and have a combined second cross-sectional area that is greater than or equal to the first cross-sectional area. A method for refurbishing the air valve, as previously described, includes increasing the second cross-sectional area greater than or equal to the first cross-sectional area.

Abstract: A drain valve includes a valve body that defines an inlet seat and a first outlet seat downstream of the inlet seat. A first member has a first position in sealing engagement with the first outlet seat and a second position separated from the first outlet seat. A second member has a first location in sealing engagement with the inlet seat. A sensor downstream of the inlet seat generates a signal reflective of a pressure downstream of the inlet seat. A method for operating a drain valve includes moving a first element in a valve body to allow fluid flow through the valve body, moving a second element in the valve body to allow fluid flow through the valve body, and sensing a pressure in the valve body.