CalCERTS is excited to offer training and certification for RESNET Standard 310. This certification allows a HERS Rater to assign a grading quality to the installation of the HVAC system.

RESNET 310: HERS Grading of HVAC Installations

The Standard applies to Unitary HVAC systems and is comprised of five tasks: a design review, a total duct leakage test, a Blower Fan volumetric airflow test, a Blower Fan watt draw test, and a noninvasive evaluation of refrigerant charge. The five tasks are designed to be completed in sequence. With the completion of each task, the results are evaluated for compliance with specified thresholds. For Task 1, these thresholds are design tolerances. For Tasks 2 through 5, the thresholds are installation quality grades. Specified thresholds must be satisfied for Tasks 1 through 3 or the subsequent tasks cannot be completed.

This Standard establishes the procedures, tolerances, and record-keeping practices for evaluating and grading elements of an HVAC system’s design and installation. It is intended to support consistency in energy rating and labeling and is for use by home energy raters, energy auditors, or HVAC contractors.