Re: [EnergyPlus_Support] Plant temperatures are getting far too hot

On Sun, Aug 25, 2013 at 6:40 PM, Denilson Espirito Santo <denilsonbes@xxxxxxxxx> wrote:

Dear Energy+ Group

I`m trying to simulate a four pipe fancoil with an electrical chiller and a boiler.

I used the fancoilautosize example file as a support.

An error is occurring (see message in the bottom).

Ideas and suggestions are appreciated.

Denilson Boschiero do Espirito Santo

Severe ** Plant temperatures are getting far too hot, check controls and relative loads and capacities
   **   ~~~   ** Environment=SAO_PAULO/CONGONHAS - BRA SWERA WMO#=837800, at Simulation time=02/20 09:15 - 09:30
   **   ~~~   ** PlantLoop Name (SupplySide)= HOT WATER LOOP
   **   ~~~   ** PlantLoop Setpoint Temperature=82.0 {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 (SupplySide) "HW SUPPLY OUTLET NODE" has temperature=300.0 {C}
   **   ~~~   ** PlantLoop Inlet Node (SupplySide) "HW SUPPLY INLET NODE" has temperature=300.0 {C}
   **   ~~~   ** PlantLoop Minimum Temperature=10.0 {C}
   **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
   **   ~~~   ** PlantLoop Flow Request (SupplySide)=0.0 {kg/s}
   **   ~~~   ** PlantLoop Flow Request (DemandSide)=0.0 {kg/s}
   **   ~~~   ** PlantLoop Node (SupplySide) "HW SUPPLY OUTLET NODE" has mass flow rate =4.7 {kg/s}
   **   ~~~   ** PlantLoop PumpHeat (SupplySide)=1088.7 {W}
   **   ~~~   ** PlantLoop PumpHeat (DemandSide)=0.0 {W}
   **   ~~~   ** PlantLoop Cooling Demand=4379245.5 {W}
   **   ~~~   ** PlantLoop Heating Demand=0.0 {W}
   **   ~~~   ** PlantLoop Demand not Dispatched=0.0 {W}
   **   ~~~   ** PlantLoop Unmet Demand=-4379245.5 {W}
   **   ~~~   ** PlantLoop Capacity=1.2 {W}
   **   ~~~   ** PlantLoop Capacity (SupplySide)=1.2 {W}
   **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
   **   ~~~   ** PlantLoop Operation Scheme=HOT LOOP OPERATION
   **   ~~~   ** PlantLoop Operation Dispatched Load = 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}
   **   ~~~   ** Branches on the Loop.
   **   ~~~   ** Demand Branches:
   **   ~~~   **   ZONESHWINLETBRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PIPE:ADIABATIC:ZONESHWINLETPIPE
   **   ~~~   **   ZONE1HWBRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       COIL:HEATING:WATER:ZONE1FANCOILHEATINGCOIL
   **   ~~~   **   ZONESHWBYPASSBRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PIPE:ADIABATIC:ZONESHWBYPASSPIPE
   **   ~~~   **   ZONESHWOUTLETBRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PIPE:ADIABATIC:ZONESHWOUTLETPIPE
   **   ~~~   ** Supply Branches:
   **   ~~~   **   HEATING SUPPLY INLET BRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PUMP:CONSTANTSPEED:HW CIRC PUMP
   **   ~~~   **   BOILER BRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       BOILER:HOTWATER:BOILER1
   **   ~~~   **   HEATING SUPPLY BYPASS BRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PIPE:ADIABATIC:HEATING SUPPLY SIDE BYPASS
   **   ~~~   **   HEATING SUPPLY OUTLET BRANCH
   **   ~~~   **     Components on Branch:
   **   ~~~   **       PIPE:ADIABATIC:HEATING SUPPLY OUTLET
   **   ~~~   ** *************************
   **   ~~~   ** Possible things to look for to correct this problem are:
   **   ~~~   **   Capacity, Operation Scheme, Mass flow problems, Pump Heat building up over time.
   **   ~~~   **   Try a shorter runperiod to stop before it fatals and look at
   **   ~~~   **     lots of node time series data to see what is going wrong.
   **   ~~~   **   If this is happening during Warmup, you can use Output:Diagnostics,ReportDuringWarmup;
   **   ~~~   **   This is detected at the loop level, but the typical problems are in the components.
   ** Fatal ** CheckForRunawayPlantTemps: Simulation terminated because of run away plant temperatures, too hot
   ...Summary of Errors that led to program termination:
   ..... Reference severe error count=1
   ..... Last severe error=Plant temperatures are getting far too hot, check controls and relative loads and capacities
   *************
   ************* ===== Recurring Error Summary =====
   ************* The following recurring error messages occurred.
   *************
   ************* ** Warning ** Plant loop exceeding upper temperature limit, PlantLoop="HOT WATER LOOP"
   ************* **   ~~~   **   This error occurred 12180 total times;
   ************* **   ~~~   **   during Warmup 116 times;
   ************* **   ~~~   **   during Sizing 0 times.
   ************* **   ~~~   **   Max=300.003706
   *************
   ************* ** Warning ** GetDensityGlycol: Temperature out of range (too high) for fluid [WATER] density **
   ************* **   ~~~   **   This error occurred 48560 total times;
   ************* **   ~~~   **   during Warmup 0 times;
   ************* **   ~~~   **   during Sizing 0 times.
   ************* **   ~~~   **   Max=300.019644 {C} Min=103.933878 {C}
   *************
   ************* ** Warning ** GetSpecificHeatGlycol: Temperature out of range (too high) for fluid [WATER] specific heat **
   ************* **   ~~~   **   This error occurred 303231 total times;
   ************* **   ~~~   **   during Warmup 0 times;
   ************* **   ~~~   **   during Sizing 0 times.
   ************* **   ~~~   **   Max=300.019644 {C} Min=125.003494 {C}
   *************
   *************
   ************* ===== Final Error Summary =====
   ************* The following error categories occurred. Consider correcting or noting.
   ************* Nominally Unused Constructions
   ************* ..The nominally unused constructions warning is provided to alert you to potential conditions that can cause
   ************* ..extra time during simulation. Each construction is calculated by the algorithm indicated in the HeatBalanceAlgorithm
   ************* ..object. You may remove the constructions indicated (when you use the DisplayExtraWarnings option).
   *************
   ************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.
   ************* EnergyPlus Sizing Error Summary. During Sizing: 3 Warning; 0 Severe Errors.
   ************* EnergyPlus Terminated--Fatal Error Detected. 363979 Warning; 1 Severe Errors; Elapsed Time=00hr 00min 36.90sec

Edwin Lee, PhD

Engineer, Commercial Buildings Research Staff

National Renewable Energy Laboratory