I have a datacenter that consumes 18 kw. For cooling I created a loop for water: Also I created a loop for air:

The simulation crash and gives me the following error:

 ** Severe  ** AirLoopHVAC VC_DATACENTER has no air flow
 **   ~~~   ** Check flow rate inputs for components in this air loop and,
 **   ~~~   ** if autosized, check Sizing:Zone and Sizing:System objects and related inputs.

I have a datacenter that consumes 18 kw. For cooling I created a loop for water: Also I created a loop for air:

error:
 ** * Severe  ** * AirLoopHVAC VC_DATACENTER has no air flow
 **  *   ~~~   ** * Check flow rate inputs for components in this air loop and,
 **  *   ~~~   ** * if autosized, check Sizing:Zone and Sizing:System objects and related inputs.