Plant overheating with Intermittent pumping

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Hi All, I’m reviewing an EnergyPlus model and have an issue which is saying “Simulation terminated because of run away plant temperatures, too hot”. I tried several methods but neither works. I’m wondering if anyone give me advice on how to address this issue. Much appreciated! Please see error message below for details of this issue and feel free to let me know if you need more information from me.

**   ~~~   ** *************************
**   ~~~   ** 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="DHW LOOP"
*************  **   ~~~   **   This error occurred 1 total times;
*************  **   ~~~   **   during Warmup 1 times;
*************  **   ~~~   **   during Sizing 0 times.
*************  **   ~~~   **   Max=1959.872626
*************
*************
************* ===== 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; 1 Severe Errors.
************* EnergyPlus Sizing Error Summary. During Sizing: 140 Warning; 0 Severe Errors.
************* EnergyPlus Terminated--Fatal Error Detected. 169 Warning; 1 Severe Errors; Elapsed Time=00hr 05min 46.73sec

Thanks again!