ProPress® 79901 Model 2981.3ZL Automatic Recirculation Balancing Valve With EPDM O-Ring, 1 in Nominal, Male BSP End Style, Bronze Body, ImportThe ProPress automatic recirculation regulating valve provides automatic balancing of domestic hot water recirculation return lines. Balancing based on hot water return temperature allows the recirculation system to run more efficiently with smaller pipes and circulators. The integrated bypass ensures that the thermal element is always sensing representative water and throttles flow accordingly. With low (I) and high (II) bypass settings, the same