Bell & Gossett W01221 Isolation Flange Three Quarters Inch

Bell & Gossett W01221 Isolation Flange 3/4" is a lead-free bronze 3/4" NPT isolation flange set designed to let you service a circulator without draining the entire hydronic loop. The kit includes two isolation flanges, capscrews and nuts for 3/4" NPT threaded connections on Bell & Gossett circulators. It is compatible with Bell & Gossett pump families such as ecocirc (ecocirc 20-18 and ecocirc+ 20-18), ecocirc XL (20-35, 36-45, 55-45 NRF/NBF/SSF), and the NRF/NBF/SSF Wet Rotor series (PL-30, PL-36, PL-55, PL-100, PR, LR). The 101221LF designation confirms lead-free construction, and Grainger lists the equivalent part as 4JA91. Installing the isolation flange on the pump discharge provides a dedicated isolation point, enabling service on the pump side while keeping the rest of the system in operation, which can simplify maintenance and valve work. The assembly is intended for use with standard Bell & Gossett flanged connections and is positioned to minimize downtime during servicing.