A structure and method of controlling building temperature are provided utilizing both solar and geo-exchange means. The trigger member may be configured for rotation between a first position and a second position and the trigger member may be able to trigger the actuator as the trigger member rotates between the first position and the second position. The voltage regulator includes an output driver, for example including first and second drive transistors, that are used in both of the selectable modes. The cable further includes a plurality of non-conductive threads, each spirally wrapped around a conductor of the plurality of conductors.