1. You should set hourly variable outputs to check and see that the chilled water is in fact resetting based on your control strategy. If you have chilled water reset in a climate that is very hot all year then an OA reset schedule will probably not show very much savings. The best way to confirm what is going on is to analyze the hourly outputs.

2. There is an option for load reset for the chilled water. However, this is not space load, this is based on the total chilled water load at the central plant.

3. I am not aware of being able to do chilled water reset by load and OA temperature at the same time. There is an option to have a schedule where you can specify the temperature. You can try to run your model once and output chilled water load and OA temperature then create a schedule for set point chilled water temperatures and work iteratively until you find something that mimics your proposed system closely. It might be time consuming but it's the best I could come up with.

John Grando BEMP | CEM | LEED AP BD+C