I am trying to implement DCV using the ProportionalControlBasedOnOccupancySchedule method in an existing IDF of mine. I have been using the I/O reference, engineering reference, and the E+ example file HeatPumpProportionalControl_DCV as guides. The example file simply chooses that method in the mechanical ventilation object and keeps all other objects including the ZoneControl:ContaminantController the same as the example file using the IAQP method (HeatPumpIAQP_DCV). The HeatPumpProportionalControl_DCV example doesn't implement a min or max CO2 concentration schedule name as suggested by the engineering reference. However after running the file it produces the expected proportional control based on occupancy.
My issue arises when mimicking the control in my IDF, regardless of my CO2 setpoint schedule (I've been using 900ppm like the example for now) my indoor CO2 concentrations are extremely low, 500-600ppm, due to my outdoor air fraction being forced to 1.0 during all occupied hours. Without DCV in my model, concentrations reach 1100-1200ppm. What would cause the OA flow fraction to be stuck at 1.0 when the concentration is well below the setpoint value? What schedules/objects are critical for the DCV method, ProportionalControlBasedOnOccupancySchedule, to be implemented? How is that setup different from using the IAQP method? Thank you.
