Siemens Building Technology 908 052 Filter Element 321042 401 Technicians should check for refrigerant Technicians should check for refrigerant in the water loop using an electronic sniffer or by isolating the heat exchanger and pressure testing the water side to confirm a breach between the refrigerant and water circuits Ensure the control shaft diameter and flat side orientation match the KIT16484 profile to guarantee a secure mechanical connection and reliable operation in demanding commercial or residential environments Is this a genuine Siemens OEM part replacing saturated elements is standard practice to prevent contaminants from fouling downstream thermostats and controllers