The iSeries mixing valves are temperature-control devices for hydronic heating systems. They provide temperature control for outdoor reset control or fixed water supply temperature. The series consists of three sizes and two-way and three-way injection configurations. According to the manufacturer, the direct-drive actuator modulates a two-way or three-way valve that injects different rates of hot water, thereby ensuring delivery of almost any water temperature to the heating system. Working off an adjustable rest ratio, a valve's maximum and minimum system supply temperatures can be adjusted to support all types of jobs, including staple-up radiant floors that require a higher starting temperature, says the company. The valves include an adjustable boiler protection function, which prevents low water temperatures from returning to the boiler, the manufacturer states.