The kit includes a TOD (Therm-O-Disc) thermostat

making it a critical component for medium and high-temperature refrigeration systems

preventing coil issues

providing a critical safety buffer for compressors by trapping excess liquid refrigerant and ensuring only vapor enters the suction port

which is critical for proper centrifugal fan operation in inducer housings

Armstrong Fluid Technology 816304-317K Plastic Impeller Els PW 17895 The kit includes a TODThe Armstrong Fluid Technology 816304 317K Plastic Impeller is a precision engineered circulator pump replacement part designed to restore peak hydraulic efficiency to your HVAC system. This 5 1 4" Noryl impeller is manufactured from high quality, non ferrous composite materials, offering superior corrosion resistance and durability in demanding hydronic applications. As the official 816304 317K maintenance kit, it serves as the direct OEM pump