Understanding and Minimizing Unmet Load Hours – A User Guide - Part 2: Spaces, Dates, and Hours subject to Unmet Load Hours tests

Part 2: Spaces, Dates, and Hours subject to Unmet Load Hours tests   

As described in Part 1 of this guide, an unmet load hour is any hour when one or more zones in the building are outside their temperature control range. Part 2 of the IES Unmet Load Hours guide describes the space attributes and mechanisms that determine which spaces, dates, and hours are subject to UMLH testing.

Topics covered in Part 2

• Space types excluded from UMLH checks
• Settings in Thermal Templates and Space Data
• Relevance of the ASHRAE-55 Comfort Analysis
•  HVAC Zones and Master Rooms
• Hours and seasonal date ranges included in automated UMLH testing

Part 3 will explain relevant user inputs and how UMLHs are calculated within the IES Virtual Environment software. Part 4 will describe the use and application of manual UMLH checks for performance assessment, tracking down sources of UMLHs, and identifying problematic HVAC zoning. Subsequent parts of the guide will present various additional strategies for minimizing UMLHs.

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You can view our other Understanding and Minimizing Unmet Load Hours articles by clicking HERE.