I'm trying to control a GroundHeatExchanger:Vertical object using SetpointManager:Scheduled:DualSetpoint so that it runs when the condenser loop drops below 50 F and when the condenser loop rises above 75 F. In between 50 F and 75 F, the condenser loop should float and the GroundHeatExchanger:Vertical should be off (no flow, no heat transfer). To do this, I took the following steps:
- Created a SetpointManager:Scheduled:DualSetpoint object and applied it to the plant side outlet node of the condenser loop. The low temperature schedule is always 50 F and the high temperature schedule is always 75 F. Note that I tried an alternate version where I applied an identical version of the same setpoint manager to the outlet node of the GroundHeatExchanger:Vertical, but it didn't seem to make any difference.
- Set the Plant Loop Demand Calculation Scheme in the condenser loop PlantLoop object to DualSetPointDeadband
- Created a PlantEquipmentOperationSchemes object with PlantEquipmentOperation:HeatingLoad and PlantEquipmentOperation:CoolingLoad objects and assigned the PlantEquipmentOperationSchemes object to the Plant Equipment Operation Scheme Name field in the condenser loop PlantLoop object. The GroundHeatExchanger:Vertical is assigned as the equipment for both the HeatingLoad and CoolingLoad control schemes and both control schemes are set to Always On.
When I run the model, it works fine on the cooling side but the GroundHeatExchanger:Vertical never comes on for heating. The condenser loop cooling and heating demand output variables look correct based on the temperature schedules assigned to the DualSetpoint manager, and GroundHeatExchanger:Vertical operation in cooling seems to sync perfectly with condenser loop cooling demand. I just can't figure out why it doesn't work in heating.