What to compare
ENERGY STAR product datasets give model-level certified records, so they are a better starting point for source-linked comparison than retailer adjectives such as quiet or whisper. source ↗ source ↗
AHRI-certified product records are another performance source, so the model or rated combination should be checked before a noise claim is repeated on a product card. source ↗
Indoor and outdoor sound should be compared separately because the indoor head affects the occupied room while the outdoor unit affects neighbors, patios, bedrooms, and property-line concerns. source ↗
Why installation still matters
A manual can specify clearances, mounting, and placement cautions, so a published sound value should not be treated as a guarantee for a poor mounting location. source ↗
Fan speed, operating mode, wall construction, pad support, and line-set contact can change perceived sound even when the equipment record is accurate. source ↗
The honest comparison is to cite the certified or manufacturer source and then ask the installer how the planned location will avoid vibration transfer and nuisance noise. source ↗ source ↗