Is it possible to transfer funds electronically from an American Credit Union to a Thai bank directly (no wire transfer)?

I sure don't know of a way. When transferring money electronically between banks in different countries, the primary way is some form of wire transfer. And even if your bank in both countries has the same bank/company name, they are still different business units since each is following the laws/rules of the country they are licensed to operate in. One of the ways that banks make money is by charging to move money around and wire transfers prove very profitable in this aspect.

Transfer of funds electronically IS a wire transfer.

Naka.