Think make sure that this (apdl commands) is only active for step 1, as the 2nd step is cooling and thus this apdl command snippet (that adds a heat source), does not need to run in the 2nd step.
See here how to select steps for the commands (so set it to First).
https://forum.ansys.com/forums/topic/step-selection-mode-for-apdl-command-in-workbench/
Erik
You are navigating away from the AIS Discovery experience