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[EnergyPlus_Support] Help with severe error of Coil:Cooling:DX

Hi,

We are encountering a problem when modelling a DX cooling coil with manufacture specs. Here is error message we received:

** Severe  ** For object = Coil:Cooling:DX:SingleSpeed, name = "COOLING COIL 1"
   **   ~~~   ** Calculated outlet air relative humidity greater than 1. The combination of
   **   ~~~   ** rated air volume flow rate, total cooling capacity and sensible heat ratio yields coil exiting
   **   ~~~   ** air conditions above the saturation curve. Possible fixes are to reduce the rated total cooling
   **   ~~~   ** capacity, increase the rated air volume flow rate, or reduce the rated sensible heat ratio for this coil.
   **   ~~~   ** If autosizing, it is recommended that all three of these values be autosized.
   **   ~~~   ** ...Inputs used for calculating cooling coil bypass factor.
   **   ~~~   ** ...Inlet Air Temperature     = 26.67 C
   **   ~~~   ** ...Outlet Air Temperature    = 12.94 C
   **   ~~~   ** ...Inlet Air Humidity Ratio  = 1.125000E-002 kgWater/kgDryAir
   **   ~~~   ** ...Outlet Air Humidity Ratio = 9.396985E-003 kgWater/kgDryAir
   **   ~~~   ** ...Total Cooling Capacity used in calculation = 89387.00 W
   **   ~~~   ** ...Air Mass Flow Rate used in calculation     = 4.766159 kg/s
   **   ~~~   ** ...Air Volume Flow Rate used in calculation   = 4.129540 m3/s
   **   ~~~   **  During Warmup, Environment=BUILDING 101 WINTER, at Simulation time=01/21 00:00 - 00:30
   **  Fatal  ** Check and revise the input data for this coil before rerunning the simulation.

The surprising thing is that the error results from the cooling coil during winter design when the dry bulb design is set at -8.4 C. EnergyPlus however output inlet air temperature, which in our system is also the mixed air temperature, at 26.67 C...  We changed our setpoint manager: scheduled and setpoint manager: mixed air exactly same as E+ example files but the error is still exist... has anyone had this problem before? Whats the possible reasons to cause this error?


Best
Weili



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