Abstract: A secondary controller that controls a secondary device and is used with a primary controller that controls a primary device. The secondary controller detects primary control signals sent to or from the primary controller, and controls the secondary device based on the detection such that the secondary device does not operate when the primary device is operating, or so that the secondary device operates in a relatively lesser capacity when the primary device is operating. Also described is an outdoor air cooling and ventilation apparatus for supplying outdoor air to an indoor space, which may optionally be used with the secondary controller.

Abstract: A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.