Where can you get a diagram for a 3.5 ton goodman air handler model aruf042-00a-1?

You can obtain a diagram for a 3.5 ton Goodman air handler model ARUF042-00A-1 from the Goodman Manufacturing website, where they provide product manuals and technical documents. Additionally, HVAC supply stores or service professionals may have access to manuals that include wiring diagrams. Online forums and DIY HVAC repair sites may also have resources or user-shared diagrams.