Dear all,

I had this discussion below a long time ago!

Basically I have a VAV system with Electric Reheat coils at the terminal
units to compensate for excessive cooling. Therefore, the reheat coils
are going to operate during the cooling season only.

Otto's advice below worked perfectly, until I decided to change the
Preheat leaving temperature from 70F to 69F (Air-Side HVAC --> Heating
--> Preheat --> Preheat Leaving Temperature) .The space heating
consumption due to diesel decreased by around 15%!

All I know is that the air is supplied to the zone at 54F. I would like
to see that the main proportion of heating is due to the hot water loop,
and a small proportion is due to the reheat coils.

Also, I do not have a conventional preheat configuration in the sense
that air is being pre-heated before going to the hot water coil.

I would like to know the exact way to model a reheat coil system for the
scenario above. I attach my file for the Preheat leaving temperature =
69F. You can change it to 70F and see the difference in Diesel Space
Heating consumption!

Many thanks for your help in advance!

Omar Katanani