[BLDG-SIM] TEMP of air leaving cool coil in equest--A confusing result!

[Mingming Zuo]

Dear all:

Hi, I modeled a VAVs in eQUEST recently and the parameters related are summarized below:

 100% outside air for all the year
 for preheat coil, PREHEAT-T=48.2 F ;
 for central cool coil, COOL-SET-T=48.2 F and MIN-SUPPLY-T=60.8F;
 for chilled water loop, loop operation = demand only.
 no economizer and heat recovery.NO humidity control!

As in Shanghai, China, there are many hours when outside air dry bulb temp will go below 48.2F, So I think no cooling from chiller is needed.After simulation, I exmained hourly 

results report and found out the CHW loop ran all the year and TEMP of air leaving cool coil is 46F. As no humidity control, in my opinion, there is no need to lower coil temp.

Why are temps of air leaving cool coil driven below 46 F while no cooling is needed?

Thanks&regards

Zuo Mingming
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