[EnergyPlus_Support] Warning for Coil:Cooling:DX:SingleSpeed

["Javednaqsh" <eee.javed@xxxxxxxxx>]

Hi All,

I am trying to run DX cooling coil and getting following repetitive error , what could be the possible solution for the same.

** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE5-1 PTAC COOLING COIL" - Full load outlet air dry-bulb temperature < 2C. This indicates the possibility of coil frost/freeze. Outlet temperature = -4.83 C.
   **   ~~~   **  ...Occurrence info = Chicago Ohare Intl Ap IL USA TMY3 WMO#=725300, 01/14 08:38 - 08:45
   **   ~~~   ** ... Possible reasons for low outlet air dry-bulb temperatures are: This DX coil
   **   ~~~   **    1) may have a low inlet air dry-bulb temperature. Inlet air temperature = 10.835 C.
   **   ~~~   **    2) may have a low air flow rate per watt of cooling capacity. Check inputs.
   **   ~~~   **    3) is used as part of a HX assisted cooling coil which uses a high sensible effectiveness. Check inputs.
   ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE3-1 PTAC COOLING COIL" - Air-cooled condenser inlet dry-bulb temperature below 0 C. Outdoor dry-bulb temperature = -4.40
   **   ~~~   **  ... Occurrence info = Chicago Ohare Intl Ap IL USA TMY3 WMO#=725300, 01/14 10:00 - 10:15
   **   ~~~   ** ... Operation at low ambient temperatures may require special performance curves.
   ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE3-1 PTAC COOLING COIL" - Full load outlet air dry-bulb temperature < 2C. This indicates the possibility of coil frost/freeze. Outlet temperature = 8.52E-002 C.
   **   ~~~   **  ...Occurrence info = Chicago Ohare Intl Ap IL USA TMY3 WMO#=725300, 01/14 10:00 - 10:15
   **   ~~~   ** ... Possible reasons for low outlet air dry-bulb temperatures are: This DX coil
   **   ~~~   **    1) may have a low inlet air dry-bulb temperature. Inlet air temperature = 15.011 C.
   **   ~~~   **    2) may have a low air flow rate per watt of cooling capacity. Check inputs.
   **   ~~~   **    3) is used as part of a HX assisted cooling coil which uses a high sensible effectiveness. Check inputs.
   ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE1-1 PTAC COOLING COIL" - Air-cooled condenser inlet dry-bulb temperature below 0 C. Outdoor dry-bulb temperature = -4.40
   **   ~~~   **  ... Occurrence info = Chicago Ohare Intl Ap IL USA TMY3 WMO#=725300, 01/14 10:45 - 11:00
   **   ~~~   ** ... Operation at low ambient temperatures may require special performance curves.
   ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE1-1 PTAC COOLING COIL" - Full load outlet air dry-bulb temperature < 2C. This indicates the possibility of coil frost/freeze. Outlet temperature = 1.79 C.
   **   ~~~   **  ...Occurrence info = Chicago Ohare Intl Ap IL USA TMY3 WMO#=725300, 01/14 15:00 - 15:15
   **   ~~~   ** ... Possible reasons for low outlet air dry-bulb temperatures are: This DX coil
   **   ~~~   **    1) may have a low inlet air dry-bulb temperature. Inlet air temperature = 15.972 C.
   **   ~~~   **    2) may have a low air flow rate per watt of cooling capacity. Check inputs.
   **   ~~~   **    3) is used as part of a HX assisted cooling coil which uses a high sensible effectiveness. Check inputs.
   ************* Simulation Error Summary *************
   *************
   ************* ===== Recurring Error Summary =====
   ************* The following recurring error messages occurred.
   *************
   *************  ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE5-1 PTAC COOLING COIL" - Low condenser dry-bulb temperature error continues...
   *************  **   ~~~   **   This error occurred 45 total times;
   *************  **   ~~~   **   during Warmup 0 times;
   *************  **   ~~~   **   during Sizing 0 times.
   *************  **   ~~~   **   Max=-2.8 [C]  Min=-7.2 [C]
   *************
   *************  ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE5-1 PTAC COOLING COIL" - Full load outlet temperature indicates a possibility of frost/freeze error continues. Outlet air temperature statistics follow:
   *************  **   ~~~   **   This error occurred 45 total times;
   *************  **   ~~~   **   during Warmup 0 times;
   *************  **   ~~~   **   during Sizing 0 times.
   *************  **   ~~~   **   Max=-2.888928  Min=-4.833602
   *************
   *************  ** Warning ** Coil:Cooling:DX:SingleSpeed "SPACE3-1 PTAC COOLING COIL" - Low condenser dry-bulb temperature error continues...
   *************  **   ~~~   **   This error occurred 26 total times;
   *************  **   ~~~   **   during Warmup 0 times;
   *************  **   ~~~   **   during Sizing 0 times.
   *************  **   ~~~   **   Max=-2.8 [C]  Min=-4.75 [C]

Any help is appreciated.

Thanks!



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