diff --git a/airflow/jobs/triggerer_job.py b/airflow/jobs/triggerer_job.py
index 1c8642986cb81..8008ece8fb215 100644
--- a/airflow/jobs/triggerer_job.py
+++ b/airflow/jobs/triggerer_job.py
@@ -382,8 +382,8 @@ def update_triggers(self, requested_trigger_ids: Set[int]):
         # handling.
         current_trigger_ids = set(self.triggers.keys())
         # Work out the two difference sets
-        new_trigger_ids = requested_trigger_ids.difference(current_trigger_ids)
-        old_trigger_ids = current_trigger_ids.difference(requested_trigger_ids)
+        new_trigger_ids = requested_trigger_ids - current_trigger_ids
+        remove_trigger_ids = current_trigger_ids - requested_trigger_ids
         # Bulk-fetch new trigger records
         new_triggers = Trigger.bulk_fetch(new_trigger_ids)
         # Add in new triggers
@@ -400,9 +400,9 @@ def update_triggers(self, requested_trigger_ids: Set[int]):
                 self.failed_triggers.append(new_id)
                 continue
             self.to_create.append((new_id, trigger_class(**new_triggers[new_id].kwargs)))
-        # Remove old triggers
-        for old_id in old_trigger_ids:
-            self.to_delete.append(old_id)
+        # Remove unneeded triggers
+        for remove_id in remove_trigger_ids:
+            self.to_delete.append(remove_id)
 
     def get_trigger_by_classpath(self, classpath: str) -> Type[BaseTrigger]:
         """