Armstrong B1671-2 Pressure Change Assembly (PCA) is a direct replacement component for Armstrong inverted bucket steam traps, configured for trap models 213 and 813, and it uses a 3/8‑inch orifice to regulate the pressure across the trap during operation. Sold as a complete PCA kit, it replaces the pressure-change mechanism that governs condensate release and trap activation, helping restore proper cycling and reduce nuisance discharge. The part is listed as B1671-2 with an F/813,213 designation, featuring a 3/8‑inch orifice and a 30# rating, and is referenced in Armstrong service literature as part of the PCA family used with multiple IB steam trap models.
