AirloopHVAC:UnitarySystem Heating with EMS

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Hey all,

I'm using an AirloopHVAC:UnitarySystem to model an RTU so I can override the heating/cooling loads using the "Sensible Load Request" for my EMS application. However, I'm seeing that the effect of this actuator is dependent on the thermostat schedule for the zone selected in the "Controlling Zone or Thermostat Location". Why is that the case? If we're overriding the sensible load request anyway, am I right in assuming a temperature setpoint should no longer be needed (or am I missing something glaringly obvious)?

Setup here:

my_load_input = OpenStudio::Model::ExternalInterfaceVariable.new(model,"my_load_input", 0)
load_actuator = OpenStudio::Model::EnergyManagementSystemActuator.new(unitaryComponent,"Unitary HVAC","Sensible Load Request")
program = OpenStudio::Model::EnergyManagementSystemProgram.new(model)
program.setName("#Load_Override_Prgm")

program_body = <<-EMS
  SET #{load_actuator.handle.to_s} = #{my_load_input.handle.to_s}
EMS
program.setBody(program_body)
pcm = OpenStudio::Model::EnergyManagementSystemProgramCallingManager.new(model)
pcm.setName("Load_Override_Prgm_Mgr")
pcm.setCallingPoint("AfterPredictorAfterHVACManagers")
pcm.addProgram(program)

Note: OpenStudio doesn't have a dxCooling-heatingGas-CVFan unitary system so I'm using the Unitary-Single Speed DX cooling-Gas heat-Cycling-Elec reheat object with the supplementary coil disabled using an Always Off schedule.

Thanks.