The Uponor Thermal Actuator is a four-wire, slow-opening thermal actuator that mounts directly onto Uponor TruFLOW™ Classic, TruFLOW Jr., Stainless-steel and Engineered Polymer (EP) Heating Manifolds for use in hydronic radiant heating and cooling systems. It provides individual loop flow control on a multi-zoned manifold and features an end switch for activation of a relay pump, heat plant, or other auxiliary devices.