- Zone control modules provide connection between thermostats and their respective actuators or zone valves as well as the connection between the end switches and the pump or boiler relay. They are compatible for use with all two-wire and four-wire Uponor actuators. The modules are internally fused for protection from over current or direct shorts from the power supply transformer. The end switch circuit is also protected from over current, and a two-amp fuse is factory installed.