A system and method to control environmental parameters of pre-defined zones within an environment using an electronic controller. An electronic controller monitors a loop temperature of a loop field of a geo-thermal heat pump as detected by a temperature sensor connected to the loop field. The electronic controller selects a staging combination of the geo-thermal heat pump and an auxiliary HVAC equipment based on at least the loop temperature. The electronic controller activates the selected staging combination, to modify at least a portion of the environmental parameters, using non-proprietary activating signals provided by the electronic controller.