RTU Evaluation Methodology

RTU Evaluation Methodology

New technologies for replacement and retrofits of existing rooftop air conditioning units offer tremendous savings opportunities. To help take advantage of those opportunities, ARC has developed a set of resources built around a streamlined RTU evaluation methodology.

  • Initial RTU Inventory: Use the RTU Inventory Spreadsheet to gather basic information (i.e., number, size, age, general condition, etc.).
  • Preliminary Screening: Organize RTUs into bins for “retrofit,” “replacement,” “no action,” or “needs further analysis” according to the results of the initial inventory and the guidance provided by the Decision Tree for RTU Replacements or Retrofits.
  • Detailed Inventory: Use the detailed fields in the RTU Inventory Spreadsheet to gather additional information (i.e., controls, usage patterns, features, etc.) for additional analysis of the RTUs identified for retrofit, replacement, or further analysis.
  • Field Evaluation: Use the RTU Field Evaluation Checklist to conduct a visual-based field evaluation to further refine the preliminary analysis.
  • Analysis: Perform energy and economic analyses to prioritize potential RTU improvements and to make the business case for taking action. Several resources are provided to assist with this analysis: RTU Incentives DatabaseRTU Comparison Calculator179D DOE CalculatorRTU Sizing Guidance, and ARC Case Studies.
  • Project Planning: Develop a plan for replacements and retrofits, which may involve working directly with a manufacturer, an Energy Service Contractor (ESCO), a full service engineering company, or an HVAC contractor. See the list of ARC Supporting Partners for manufacturers and service providers.
  • Procurement: Prepare a procurement specification(s) for replacement or retrofit of RTUs. Incorporation of quality installation and quality maintenance requirements in the procurement specification is recommended; see sample specifications for guidance.
  • Measurement and Verification (M&V): Use the M&V Guidance Document to determine the appropriate level of M&V for the project and develop and M&V plan.