From 1996 to 2002 he studied for a business administration (REFA-Betriebswirt) with a focus on productivity improvement and process optimization at the REFA-Institut Darmstadt / Dortmund.

In 1997 he trained in labour, tariff classification and legislation at the Pedagogical Institute for the Economy in Bebra.

Alongside his job at the Thuringian Institute for Curriculum Development, Teacher Training and Media (ThILLM), Weiler pursued studies from 2007 to 2009 at the Free University of Berlin, earning a master's degree in public policy.

In the 2013 federal election, Weiler won the direct mandate for the CDU in the constituency Gera – Jena – Saale-Holzland-Kreis.

In addition to his committee assignments, Weiler served as deputy chairman of the Parliamentary Friendship Group for Relations with the States of the Southern Caucasus (2018–2021) and as member of the Parliamentary Friendship Group for Relations with the SADC States (2013-2017).