The eQuest help file says that for chilled water loops (and most other
loops), a process load sign does not matter - the program automatically
assumes it is a heat load to the loop. However, I am trying to model
chilled water return preheat for a 100% outside air system, and it would
be very convenient if I could actually subtract heat from the loop via a
negative process load.

Does anyone know if there is a work around to this?

Likewise, for free-cooling in a chilled water system: I've always
modeled this by creating a free-cooling chiller (with almost infinite
efficiency), and used load management to force the use of this chiller
when the ambient temperature is below 45 degrees. However, if I could
impart a negative value to a chilled water loop, then I could simply
create a process load schedule based on weather data, and I could use
that for every free-cooling project with minimal work.

Any thoughts?

Thanks,

James Hansen, PE, LEED AP