<p>Dear folks,<br> <br>I am simulating an office building to be LEED-certified.<br> <br>The system for the proposed design is VAV+baseboard radiation. The system contains no reheating and preheating.<br> <br>The system for the baseline is VAV with reheat, but without preheat.<br>
<br>The unmet load hours for both models are significant and sim file outputs warnings as below:<br> <br>"Warning message"</p>
<p> **WARNING**********************************************************************<br> PREHEAT/HEATING-CAPACITY in SYSTEM E1 Sys1 (VAVS) <br> is too low to provide the requested supply temperature for<br>
the calculated mixed air temperature using total ZONE loads<br> (on LS-A/B) and SYSTEM design parameters, plus outside air<br> conditions (on LS-C), and specified capacities & air flows.<br>
Requested temperature is 52.00 calculated is 48.87<br> Check HEATING-CAPACITY, HEAT-SET-T, PRE-HEAT-T, MAX-SUPPLY-T,<br> DESIGN-HEAT-T, and ZONE loads for consistency.</p>
<p> <br>I am wondering if any expert could tell me what accounts for warnings and the high unmet load hours, and how to reduce it. <br> <br>Thank you<br> <br>Jessi Xu</p>