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Preventing simultaneous heating and cooling in OpenStudio

Hello. I am working on a residential home with two HVAC units - a gas furnace for heating and a whole house fan for cooling. The heating setpoint is 69 deg and the cooling setpoint is 78 deg. For their HVAC operation schedules, I selected "Always Off" and set night cycle to be "Cycle on Full System if Heating or Cooling Required" - I did this to activate the units only when the zone setpoints are not met. image description

However, I noticed in the results that both heating and cooling were activated at the same time. It looks like heating would also turn on when cooling is needed and vice-versa. I concluded this by seeing that 1) zone conditions were worse than when there was no unit at all, 2) gas consumption was higher during the summer. I am guessing OpenStudio does not separate heating and cooling requirements. Also, I don't think OS realizes that the gas furnace unit is heating only and the house fan is cooling only. I have the unit screenshots below along with their setpoint managers - maybe I am using wrong setpoint managers? I took the min and max values as desired zone temperature ranges.

image description image description

Would there be a good strategy to prevent simultaneous heating and cooling in my model? There is no set unit on/off schedule as the operations solely depend on meeting the temperature setpoints. Also the home occupancy is 100%.

Thank you so much!

Preventing simultaneous heating and cooling in OpenStudio

Hello. I am working on a residential home with two HVAC units - a gas furnace for heating and a whole house fan for cooling. The heating setpoint is 69 deg and the cooling setpoint is 78 deg. For their HVAC operation schedules, I selected "Always Off" and set night cycle to be "Cycle on Full System if Heating or Cooling Required" - I did this to activate the units only when the zone setpoints are not met. image description

However, I noticed in the results that both heating and cooling were activated at the same time. It looks like heating would also turn on when cooling is needed and vice-versa. I concluded this by seeing that 1) zone conditions were worse than when there was no unit at all, 2) gas consumption was higher during the summer. I am guessing OpenStudio does not separate heating and cooling requirements. Also, I don't think OS realizes that the gas furnace unit is heating only and the house fan is cooling only. I have the unit screenshots below along with their setpoint managers - maybe I am using wrong setpoint managers? I took the min and max values as desired zone temperature ranges.

image description image description

Would there be a good strategy to prevent simultaneous heating and cooling in my model? There is no set unit on/off schedule as the operations solely depend on meeting the temperature setpoints. Also the home occupancy is 100%.

Thank you so much!

Preventing simultaneous heating and cooling in OpenStudio

Hello. I am working on a residential home with two HVAC units - a gas furnace for heating and a whole house fan for cooling. The heating setpoint is 69 deg and the cooling setpoint is 78 deg. For their HVAC operation schedules, I selected "Always Off" and set night cycle to be "Cycle on Full System if Heating or Cooling Required" - I did this to activate the units only when the zone setpoints are not met. image description

However, I noticed in the results that both heating and cooling were activated at the same time. It looks like heating would also turn on when cooling is needed and vice-versa. I concluded this by seeing that 1) zone conditions were worse than when there was no unit at all, 2) gas consumption was higher during the summer. I am guessing OpenStudio does not separate heating and cooling requirements. Also, I don't think OS realizes that the gas furnace unit is heating only and the house fan is cooling only. I have the unit screenshots below along with their setpoint managers - maybe I am using wrong setpoint managers? I took the min and max values as desired zone temperature ranges.

image description image description

Would there be a good strategy to prevent simultaneous heating and cooling in my model? There is no set unit on/off schedule as the operations solely depend on meeting the temperature setpoints. Also the home occupancy is 100%.

Thank you so much!

Preventing simultaneous heating and cooling in OpenStudio

Hello. I am working on a residential home with two HVAC units - a gas furnace for heating and a whole house fan for cooling. The heating setpoint is 69 deg and the cooling setpoint is 78 deg. For their HVAC operation schedules, I selected "Always Off" and set night cycle to be "Cycle on Full System if Heating or Cooling Required" - I did this to activate the units only when the zone setpoints are not met. image description

However, I noticed in the results that both heating and cooling were activated at the same time. It looks like heating would also turn on when cooling is needed and vice-versa. I concluded this by seeing that 1) zone conditions were worse than when there was no unit at all, 2) gas consumption was higher during the summer. I am guessing OpenStudio does not separate heating and cooling requirements. Also, I don't think OS realizes that the gas furnace unit is heating only and the house fan is cooling only. I have the unit screenshots below along with their setpoint managers - maybe I am using wrong setpoint managers? I took the min and max values as desired zone temperature ranges.

image description image description

Would there be a good strategy to prevent simultaneous heating and cooling in my model? There is no set unit on/off schedule as the operations solely depend on meeting the temperature setpoints. Also the home occupancy is 100%.

Thank you so much!