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Hello,

Good day to all.

I am modeling an HVAC system for an offices building with 8 floors which has several AHUs and FCUs installed. The simulation stops with the following error (Copied as is):

QUOTE

* Severe * Plant temperatures are getting far too hot, check controls and relative loads and capacities

* ~~~ * PlantLoop Name (DemandSide)= HOT WATER LOOP

* ~~~ * PlantLoop Setpoint Temperature=67.0 {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 134" has temperature=300.1 {C}

* ~~~ * PlantLoop Inlet Node (DemandSide) "NODE 133" has temperature=300.2 {C}

* ~~~ * PlantLoop Minimum Temperature=0.0 {C}

* ~~~ * PlantLoop Maximum Temperature=100.0 {C}

* ~~~ * PlantLoop Flow Request (SupplySide)=6.9 {kg/s}

* ~~~ * PlantLoop Flow Request (DemandSide)=0.6 {kg/s}

* ~~~ * PlantLoop Node (DemandSide) "NODE 134" has mass flow rate =0.6 {kg/s}

* ~~~ * PlantLoop PumpHeat (SupplySide)=1982.2 {W}

* ~~~ * PlantLoop PumpHeat (DemandSide)=185.5 {W}

* ~~~ * PlantLoop Cooling Demand=6855817.6 {W}

* ~~~ * PlantLoop Heating Demand=0.0 {W}

* ~~~ * PlantLoop Demand not Dispatched=0.0 {W}

* ~~~ * PlantLoop Unmet Demand=-6855817.6 {W}

* ~~~ * PlantLoop Capacity=411062.5 {W}

* ~~~ * PlantLoop Capacity (SupplySide)=411062.5 {W}

* ~~~ * PlantLoop Capacity (DemandSide)=0.0 {W}

* ~~~ * PlantLoop Operation Scheme=HOT WATER LOOP OPERATION SCHEMES

* ~~~ * PlantLoop Operation Dispatched Load = 0.0 {W}

* ~~~ * PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}

* ~~~ * PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

UNQUOTE

I read the other posts asking questions related to what I am asking too but I wasn't able to locate the problem.

The following are photos for the supply/demand of the loop (There are a lot of heating coils so I took two screenshots showing the essentials):

The outlet node supply side set point is set to 80 C. The pumps are intermittent. Both AHUs and FCUs coils inlet water temperatures are set to 80 C and outlet water temperatures to 69 C. The AHUs coils capacities range between 5 kw to 10 kw (I have about 11 coils for the AHUs). The boiler design flow rate is auto-sized. The plant design loop exit temperature is 80 C and loop design temperature difference is 11 C.

I can't seem to solve my problem. Can you assist ?

Many thanks in advance.

Hello,

Good day to all.

I am modeling an HVAC system for an offices building with 8 floors which has several AHUs and FCUs installed. The simulation stops with the following error (Copied as is):

   ** Severe  * ** Plant temperatures are getting far too hot, check controls and relative loads and capacities
 
*   ~~~   * capacities
   **   ~~~   ** PlantLoop Name (DemandSide)= HOT WATER LOOP
 
*   ~~~   * LOOP
   **   ~~~   ** PlantLoop Setpoint Temperature=67.0 {C}
 
*   ~~~   * {C}
   **   ~~~   ** PlantLoop Inlet Node (SupplySide) does not have a Setpoint.
 
*   ~~~   * Setpoint.
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) does not have a Setpoint.
 
*   ~~~   * Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (SupplySide) has a Setpoint.
 
*   ~~~   * Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (DemandSide) does not have a Setpoint.
 
*   ~~~   * Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (DemandSide) "NODE 134" has temperature=300.1 {C}
 
*   ~~~   * {C}
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) "NODE 133" has temperature=300.2 {C}
 
*   ~~~   * {C}
   **   ~~~   ** PlantLoop Minimum Temperature=0.0 {C}
 
*   ~~~   * {C}
   **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
 
*   ~~~   * {C}
   **   ~~~   ** PlantLoop Flow Request (SupplySide)=6.9 {kg/s}
 
*   ~~~   * {kg/s}
   **   ~~~   ** PlantLoop Flow Request (DemandSide)=0.6 {kg/s}
 
*   ~~~   * {kg/s}
   **   ~~~   ** PlantLoop Node (DemandSide) "NODE 134" has mass flow rate =0.6 {kg/s}
 
*   ~~~   * {kg/s}
   **   ~~~   ** PlantLoop PumpHeat (SupplySide)=1982.2 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop PumpHeat (DemandSide)=185.5 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Cooling Demand=6855817.6 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Heating Demand=0.0 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Demand not Dispatched=0.0 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Unmet Demand=-6855817.6 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Capacity=411062.5 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Capacity (SupplySide)=411062.5 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Operation Scheme=HOT WATER LOOP OPERATION SCHEMES
 
*   ~~~   * SCHEMES
   **   ~~~   ** PlantLoop Operation Dispatched Load = 0.0 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}
 
*   ~~~   * {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}
 
UNQUOTE{W}

Hello,

Good day to all.

I am modeling an HVAC system for an offices building with 8 floors which has several AHUs and FCUs installed. The simulation stops with the following error (Copied as is):

   ** Severe  ** Plant temperatures are getting far too hot, check controls and relative loads and capacities
   **   ~~~   ** PlantLoop Name (DemandSide)= HOT WATER LOOP
   **   ~~~   ** PlantLoop Setpoint Temperature=67.0 {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 134" has temperature=300.1 {C}
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) "NODE 133" has temperature=300.2 {C}
   **   ~~~   ** PlantLoop Minimum Temperature=0.0 {C}
   **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
   **   ~~~   ** PlantLoop Flow Request (SupplySide)=6.9 {kg/s}
   **   ~~~   ** PlantLoop Flow Request (DemandSide)=0.6 {kg/s}
   **   ~~~   ** PlantLoop Node (DemandSide) "NODE 134" has mass flow rate =0.6 {kg/s}
   **   ~~~   ** PlantLoop PumpHeat (SupplySide)=1982.2 {W}
   **   ~~~   ** PlantLoop PumpHeat (DemandSide)=185.5 {W}
   **   ~~~   ** PlantLoop Cooling Demand=6855817.6 {W}
   **   ~~~   ** PlantLoop Heating Demand=0.0 {W}
   **   ~~~   ** PlantLoop Demand not Dispatched=0.0 {W}
   **   ~~~   ** PlantLoop Unmet Demand=-6855817.6 {W}
   **   ~~~   ** PlantLoop Capacity=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (SupplySide)=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
   **   ~~~   ** PlantLoop Operation Scheme=HOT WATER LOOP OPERATION SCHEMES
   **   ~~~   ** PlantLoop Operation Dispatched Load = 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

I read the other posts asking questions related to what I am asking too but I wasn't able to locate the problem.

The following are photos for the supply/demand of the loop (There are a lot of heating coils so I took two screenshots showing the essentials):

The outlet node supply side set point is set to 80 C. The pumps are intermittent. Both AHUs and FCUs coils inlet water temperatures are set to 80 C and outlet water temperatures to 69 C. The AHUs coils capacities range between 5 kw to 10 kw (I have about 11 coils for the AHUs). The boiler design flow rate is auto-sized. The plant design loop exit temperature is 80 C and loop design temperature difference is 11 C.

I can't seem to solve my problem. Can you assist ?

Many thanks in advance.

Hello,

Good day to all.

I am modeling an HVAC system for an offices building with 8 floors which has several AHUs and FCUs installed. The simulation stops with the following error (Copied as is):

   ** Severe  ** Plant temperatures are getting far too hot, check controls and relative loads and capacities
   **   ~~~   ** PlantLoop Name (DemandSide)= HOT WATER LOOP
   **   ~~~   ** PlantLoop Setpoint Temperature=67.0 {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 134" has temperature=300.1 {C}
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) "NODE 133" has temperature=300.2 {C}
   **   ~~~   ** PlantLoop Minimum Temperature=0.0 {C}
   **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
   **   ~~~   ** PlantLoop Flow Request (SupplySide)=6.9 {kg/s}
   **   ~~~   ** PlantLoop Flow Request (DemandSide)=0.6 {kg/s}
   **   ~~~   ** PlantLoop Node (DemandSide) "NODE 134" has mass flow rate =0.6 {kg/s}
   **   ~~~   ** PlantLoop PumpHeat (SupplySide)=1982.2 {W}
   **   ~~~   ** PlantLoop PumpHeat (DemandSide)=185.5 {W}
   **   ~~~   ** PlantLoop Cooling Demand=6855817.6 {W}
   **   ~~~   ** PlantLoop Heating Demand=0.0 {W}
   **   ~~~   ** PlantLoop Demand not Dispatched=0.0 {W}
   **   ~~~   ** PlantLoop Unmet Demand=-6855817.6 {W}
   **   ~~~   ** PlantLoop Capacity=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (SupplySide)=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
   **   ~~~   ** PlantLoop Operation Scheme=HOT WATER LOOP OPERATION SCHEMES
   **   ~~~   ** PlantLoop Operation Dispatched Load = 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

I read the other posts asking questions related to what I am asking too but I wasn't able to locate the problem.

The following are photos for the supply/demand of the loop (There are a lot of heating coils so I took two screenshots showing the essentials):

The outlet node supply side set point is set to 80 C. The pumps are intermittent. Both AHUs and FCUs coils inlet water temperatures are set to 80 C and outlet water temperatures to 69 C. The AHUs coils capacities range between 5 kw to 10 kw (I have about 11 coils for the AHUs). The boiler design flow rate is auto-sized. The plant design loop exit temperature is 80 C and loop design temperature difference is 11 C.

I can't seem to solve my problem. Can you assist ?

Many thanks in advance.