What is the difference between AAMA 501.2 and ASTM E1105?
AAMA 501.2 is a field check that sprays water from a calibrated nozzle along joints of installed storefronts, curtain walls and sloped glazing, with an observer inside. It uses no air pressure difference. ASTM E1105 applies water to the outside of installed windows, skylights, doors or curtain walls while a chamber creates a static air pressure difference across the assembly, simulating wind-driven rain. E1105 is more representative of storms but needs a sealed chamber.
From the RRD Field Guide, checked against the sources cited in Façade and Curtain Wall Water Leakage: How to Diagnose and Fix the Root Cause. General information, not advice for your project.
The fuller picture
Façade leaks are diagnosed by mapping when and where water appears, ruling out non-façade sources, then reproducing the leak with controlled water tests: AAMA 501.2 nozzle testing for curtain walls and ASTM E1105 pressure-chamber testing for windows and walls. Test from the bottom up, isolate one joint at a time, and repair the proven path rather than re-sealing everything.