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What is the difference between average and minimum ventilation when demand controlled ventilation is not enabled?

A few notes about my model in particular:

  • I currently have the design specification outdoor air rate set to 20 cfm/person
  • The HVAC system shuts down entirely overnight and on weekends
  • Occupancy significantly drops, but is not always at 0 when the HVAC system is off (so hours with system on and occupied hours are not exactly one to one).
  • I'm assuming that (by default) if the HVAC system is off, OpenStudio knows not to supply outdoor air(?)

Both the avg. and min. values are reasonably close to the singular value I had calculated, by hand, for each of the zones' ventilation rate (for example, for the second row I had previously calculated 7.17 ACH).

Thanks!

image description

What is the difference between average and minimum ventilation when demand controlled ventilation is not enabled?

A few notes about my model in particular:

  • I currently have the design specification outdoor air rate set to 20 cfm/person
  • The HVAC system shuts down entirely overnight and on weekends
  • Occupancy significantly drops, but is not always at 0 when the HVAC system is off (so hours with system on and occupied hours are not exactly one to one).
  • I'm assuming that (by default) if the HVAC system is off, OpenStudio knows not to supply outdoor air(?)

Both the avg. and min. values are reasonably close to the singular value I had calculated, by hand, for each of the zones' ventilation rate (for example, for the second row I had previously calculated 7.17 ACH).

Thanks!

image description