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Hi all,

I am modeling an HVAC system based on a Central Heat Pump System. The system is used to fulfill both cooling as well as heating requirement of the building.

In this scenario, I have modeled two buildings in two separate energy models and run the simulation using District cooling and heating components. These buildings are basically served by a single HVAC plant so I take out the cooling and heating load profiles of these buildings and use it in a separate model by the help of LoadProfile:Plant object. In this model, I modeled the actual HVAC plant along with Central Heat Pump System to fulfill the cooling as well as heating requirement.

While running the simulation I am getting an error

* Severe * Plant temperatures are getting far too cold, check controls and relative loads and capacities * ~~~ * During Warmup, Environment=RUN PERIOD 1, at Simulation time=01/01 17:00 - 18:00 * ~~~ * PlantLoop Name (DemandSide)= HW PLANT LOOP * ~~~ * PlantLoop Setpoint Temperature=48.9 {C} * ~~~ * PlantLoop Inlet Node (SupplySide) does not have a Setpoint. * ~~~ * PlantLoop Inlet Node (DemandSide) does not have a Setpoint. * ~~~ * PlantLoop Outlet Node (SupplySide) has a Setpoint. * ~~~ * PlantLoop Outlet Node (DemandSide) does not have a Setpoint. * ~~~ * PlantLoop Outlet Node (DemandSide) "NODE 40" has temperature=-103.0 {C} * ~~~ * PlantLoop Inlet Node (DemandSide) "NODE 39" has temperature=-102.7 {C} * ~~~ * PlantLoop Minimum Temperature=5.7E-014 {C} * ~~~ * PlantLoop Maximum Temperature=100.0 {C} * ~~~ * PlantLoop Flow Request (SupplySide)=12.0 {kg/s} * ~~~ * PlantLoop Flow Request (DemandSide)=1.8 {kg/s} * ~~~ * PlantLoop Node (DemandSide) "NODE 40" has mass flow rate =12.0 {kg/s} * ~~~ * PlantLoop PumpHeat (SupplySide)=4138.6 {W} * ~~~ * PlantLoop PumpHeat (DemandSide)=0.0 {W} * ~~~ * PlantLoop Cooling Demand=0.0 {W} * ~~~ * PlantLoop Heating Demand=7676447.2 {W} * ~~~ * PlantLoop Demand not Dispatched=5086447.2 {W} * ~~~ * PlantLoop Unmet Demand=7675426.1 {W} * ~~~ * PlantLoop Capacity=2590000.0 {W} * ~~~ * PlantLoop Capacity (SupplySide)=2590000.0 {W} * ~~~ * PlantLoop Capacity (DemandSide)=0.0 {W} * ~~~ * PlantLoop Operation Scheme=HW PLANT LOOP OPERATION SCHEMES * ~~~ * PlantLoop Operation Dispatched Load = 2590000.0 {W} * ~~~ * PlantLoop Operation Dispatched Load (SupplySide)= 2590000.0 {W} * ~~~ * PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

I am trying to solve it but unable to figure out. I appreciate your help.

Hi all,

I am modeling an HVAC system based on a Central Heat Pump System. The system is used to fulfill both cooling as well as heating requirement of the building.

In this scenario, I have modeled two buildings in two separate energy models and run the simulation using District cooling and heating components. These buildings are basically served by a single HVAC plant so I take out the cooling and heating load profiles of these buildings and use it in a separate model by the help of LoadProfile:Plant object. In this model, I modeled the actual HVAC plant along with Central Heat Pump System to fulfill the cooling as well as heating requirement.

While running the simulation I am getting an error

** Severe  * ** Plant temperatures are getting far too cold, check controls and relative loads and capacities
 *   ~~~   * **   ~~~   **  During Warmup, Environment=RUN PERIOD 1, at Simulation time=01/01 17:00 - 18:00
 *   ~~~   * **   ~~~   ** PlantLoop Name (DemandSide)= HW PLANT LOOP
 *   ~~~   * **   ~~~   ** PlantLoop Setpoint Temperature=48.9 {C}
 *   ~~~   * **   ~~~   ** PlantLoop Inlet Node (SupplySide) does not have a Setpoint.
 *   ~~~   * **   ~~~   ** PlantLoop Inlet Node (DemandSide) does not have a Setpoint.
 *   ~~~   * **   ~~~   ** PlantLoop Outlet Node (SupplySide) has a Setpoint.
 *   ~~~   * **   ~~~   ** PlantLoop Outlet Node (DemandSide) does not have a Setpoint.
 *   ~~~   * **   ~~~   ** PlantLoop Outlet Node (DemandSide) "NODE 40" has temperature=-103.0 {C}
 *   ~~~   * **   ~~~   ** PlantLoop  Inlet Node (DemandSide) "NODE 39" has temperature=-102.7 {C}
 *   ~~~   * **   ~~~   ** PlantLoop Minimum Temperature=5.7E-014 {C}
 *   ~~~   * **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
 *   ~~~   * **   ~~~   ** PlantLoop Flow Request (SupplySide)=12.0 {kg/s}
 *   ~~~   * **   ~~~   ** PlantLoop Flow Request (DemandSide)=1.8 {kg/s}
 *   ~~~   * **   ~~~   ** PlantLoop Node (DemandSide) "NODE 40" has mass flow rate =12.0 {kg/s}
 *   ~~~   * **   ~~~   ** PlantLoop PumpHeat (SupplySide)=4138.6 {W}
 *   ~~~   * **   ~~~   ** PlantLoop PumpHeat (DemandSide)=0.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Cooling Demand=0.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Heating Demand=7676447.2 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Demand not Dispatched=5086447.2 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Unmet Demand=7675426.1 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Capacity=2590000.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Capacity (SupplySide)=2590000.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Operation Scheme=HW PLANT LOOP OPERATION SCHEMES
 *   ~~~   * **   ~~~   ** PlantLoop Operation Dispatched Load = 2590000.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 2590000.0 {W}
 *   ~~~   * **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}
{W}

Hi all,

I am modeling an HVAC system based on a Central Heat Pump System. The system is used to fulfill both cooling as well as heating requirement of the building.

In this scenario, I have modeled two buildings in two separate energy models and run the simulation using District cooling and heating components. These buildings are basically served by a single HVAC plant so I take out the cooling and heating load profiles of these buildings and use it in a separate model by the help of LoadProfile:Plant object. In this model, I modeled the actual HVAC plant along with Central Heat Pump System to fulfill the cooling as well as heating requirement.

While running the simulation I am getting an error

** Severe  ** Plant temperatures are getting far too cold, check controls and relative loads and capacities
**   ~~~   **  During Warmup, Environment=RUN PERIOD 1, at Simulation time=01/01 17:00 - 18:00
**   ~~~   ** PlantLoop Name (DemandSide)= HW PLANT LOOP
**   ~~~   ** PlantLoop Setpoint Temperature=48.9 {C}
**   ~~~   ** PlantLoop Inlet Node (SupplySide) does not have a Setpoint.
**   ~~~   ** PlantLoop Inlet Node (DemandSide) does not have a Setpoint.
**   ~~~   ** PlantLoop Outlet Node (SupplySide) has a Setpoint.
**   ~~~   ** PlantLoop Outlet Node (DemandSide) does not have a Setpoint.
**   ~~~   ** PlantLoop Outlet Node (DemandSide) "NODE 40" has temperature=-103.0 {C}
**   ~~~   ** PlantLoop  Inlet Node (DemandSide) "NODE 39" has temperature=-102.7 {C}
**   ~~~   ** PlantLoop Minimum Temperature=5.7E-014 {C}
**   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
**   ~~~   ** PlantLoop Flow Request (SupplySide)=12.0 {kg/s}
**   ~~~   ** PlantLoop Flow Request (DemandSide)=1.8 {kg/s}
**   ~~~   ** PlantLoop Node (DemandSide) "NODE 40" has mass flow rate =12.0 {kg/s}
**   ~~~   ** PlantLoop PumpHeat (SupplySide)=4138.6 {W}
**   ~~~   ** PlantLoop PumpHeat (DemandSide)=0.0 {W}
**   ~~~   ** PlantLoop Cooling Demand=0.0 {W}
**   ~~~   ** PlantLoop Heating Demand=7676447.2 {W}
**   ~~~   ** PlantLoop Demand not Dispatched=5086447.2 {W}
**   ~~~   ** PlantLoop Unmet Demand=7675426.1 {W}
**   ~~~   ** PlantLoop Capacity=2590000.0 {W}
**   ~~~   ** PlantLoop Capacity (SupplySide)=2590000.0 {W}
**   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
**   ~~~   ** PlantLoop Operation Scheme=HW PLANT LOOP OPERATION SCHEMES
**   ~~~   ** PlantLoop Operation Dispatched Load = 2590000.0 {W}
**   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 2590000.0 {W}
**   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

I am trying to solve it but unable to figure out. I appreciate your help.