Systems Analysis | Zone Load Summary and System Load Summary

[michel_martinss]

After the simulation is done by the heat balance method, we have the zone load summary and the system load summary. The difference from one to the other is basically the inclusion of the outer air load portion in the system. Why in the properties when selecting the analytical space the value that appears in the Peak Cooling Load is the thermal load that takes into account only the envelope loads and internal gains (Zone Load Summary)? The same thing happens for Schedules analytical space. I know we can see the actual load (envelope + internal gains + Systems) by system load summary, but it would be interesting these values to be sampled in the analytical spaces and visible in tables. A person with no experience in this can scale the system in the wrong way.

[iainsavage]

By outdoor air do you mean the fresh air component brought in at the air handling unit?

If that is the case then it would be incorrect to apportion that load to the spaces since it is a load on the coil at the AHU rather than a gain/loss in the space.

If its fabric infiltration rate in the space or passive ventilation directly to the space rather than via an AHU then that should be apportioned to the space.

To be honest though I've never fully understood how Revit/OpenStudio deals with these loads and I think there have been previous posts in a similar vein.