Question-and-Answer Resource for the Building Energy Modeling Community
Get s tarted with the Help page
Ask Your Question

Revision history [back]

Best output:variable for zone heating / cooling load

I thought I knew what I was doing.... but now I'm not sure.

I want an hour-by-hour representation of the total heating load and total cooling load for DOE reference buildings. It seemed to me that "Zone Predicted Sensible Load to Setpoint Heat Transfer Rate" would be perfect; add up all the positive values for heating load and all negative values for cooling load. (The definition is shown at the bottom of this post.)

This approach, after reviewing results, is suspect. I'm looking at the Hospital results and see that the Operating Rooms, which are on an exterior wall and the 2nd floor, NEVER have a cooling load. In fact, they have a few heating load hours, but show zero load for the vast majority of hours. This is true despite having substantial lighting, plug and people loads.

Can you provide a suggestion for: * what I may be missing in my understanding of the variable? or * a better approach?

Thanks in advance.

Zone Predicted Sensible Load to Setpoint Heat Transfer Rate [W] This is the predicted sensible load in W required to meet the current zone thermostat setpoint. A positive value indicates a heating load, a negative value indicates a cooling load. This is calculated and reported from the Predict step in the Zone Predictor-Corrector module. For nearly all equipment types, the Predictor-Corrector evaluates the active heating and/or cooling setpoints, determines if the zone requires heating or cooling or is in the deadband, and then passes this single load to the equipment. This value is not multiplied by zone or group multipliers.

Best output:variable for zone heating / cooling load

I thought I knew what I was doing.... but now I'm not sure.

I want an hour-by-hour representation of the total heating load and total cooling load for DOE reference buildings. It seemed to me that "Zone Predicted Sensible Load to Setpoint Heat Transfer Rate" would be perfect; add up all the positive values for heating load and all negative values for cooling load. (The definition is shown at the bottom of this post.)

This approach, after reviewing results, is suspect. I'm looking at the Hospital results and see that the Operating Rooms, which are on an exterior wall and the 2nd floor, NEVER have a cooling load. In fact, they have a few heating load hours, but show zero load for the vast majority of hours. This is true despite having substantial lighting, plug and people loads.

Can you provide a suggestion for: * for:

  • what I may be missing in my understanding of the variable? or * or
  • a better approach?

Thanks in advance.

Zone Predicted Sensible Load to Setpoint Heat Transfer Rate [W] This is the predicted sensible load in W required to meet the current zone thermostat setpoint. A positive value indicates a heating load, a negative value indicates a cooling load. This is calculated and reported from the Predict step in the Zone Predictor-Corrector module. For nearly all equipment types, the Predictor-Corrector evaluates the active heating and/or cooling setpoints, determines if the zone requires heating or cooling or is in the deadband, and then passes this single load to the equipment. This value is not multiplied by zone or group multipliers.

Best output:variable for zone heating / cooling load

I thought I knew what I was doing.... but now I'm not sure.

I want an hour-by-hour representation of the total heating load and total cooling load for DOE reference buildings. It seemed to me that "Zone Predicted Sensible Load to Setpoint Heat Transfer Rate" would be perfect; add up all the positive values for heating load and all negative values for cooling load. (The definition is shown at the bottom of this post.)

This approach, after reviewing results, is suspect. I'm looking at the Hospital results and see that the Operating Rooms, which are on an exterior wall and the 2nd floor, NEVER have a cooling load. In fact, they have a few heating load hours, but show zero load for the vast majority of hours. This is true despite having substantial lighting, plug and people loads.

Can you provide a suggestion for:

  • what I may be missing in my understanding of the variable? or
  • a better approach?

Thanks in advance.

Zone Predicted Sensible Load to Setpoint Heat Transfer Rate [W] This is the predicted sensible load in W required to meet the current zone thermostat setpoint. A positive value indicates a heating load, a negative value indicates a cooling load. This is calculated and reported from the Predict step in the Zone Predictor-Corrector module. For nearly all equipment types, the Predictor-Corrector evaluates the active heating and/or cooling setpoints, determines if the zone requires heating or cooling or is in the deadband, and then passes this single load to the equipment. This value is not multiplied by zone or group multipliers.