MXE21.20U/180 Electromotoric 3-port zone valve AC 230 V on/off 2-position control signal, auxiliary switch
PN16, DN20, kvs = 4 m3/h, dpmax = 70 kPa. 
Key data to replacement product: 3-port valve PN16, DN20, kvs = 3.5 m3/h, dpmax = 100 kPa. (
Key data to replacement product: valve has different direction of flow). 
Info: Electromotoric actuator SFA21/18 and auxiliary switch ASC2.1/18 also needed.