There are currently two reference manuals for how to calculate the annual energy performance values for AERC certified products.

User Documentation
 

• AERC WINDOW/THERM Simulation Manual (PDF)
• AERCalc User Guide (PDF)

Technical Documentation
 

• Energy Performance Indices EPc and EPh Calculation Methodology and Implementation in Software Tool (PDF)

In addition, there are videos from the initial user training that was given at LBNL.