Title 24 and evaporative pre-cooling

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Hi everyone,

I am working on a California project pursuing Title-24 2008 and using
eQuest for the analysis. The project includes VAV with chilled water
cooling and hot water reheat system . Additionally the system is 100% OA
system and also includes indirect evaporative pre-cooling in the design. My
model indicates that the evaporative pre-cooling is helping on the cooling
energy savings ( as expected) but I am getting heating penalty because of
it.

After digging into the simulation output reports it seems that the reheat
energy has increased significantly and the space temperature for the zones
have more hours in the cooling temperature band. I believe that the
evaporative pre-cooling is overcooling the spaces. Further, I think that
the evaporative pre-cooling is treating OA with dry bulb as low as 55F.

Can somebody please suggest how to control the evaporative pre-cooling so
that it comes on for OA above 70F temperature only. eQuest has a high limit
set point for evaporative pre coolers but no low limit one. Also, any
thoughts on how to control the increase in reheat energy.

Thank you

Nidhi

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