Both the PVS-IS2 at https://pvcventscreens.com/product/pv... and PVS-IS3 at https://pvcventscreens.com/product/pv... are designed to prevent bees and wasps from nesting inside furnace intake and exhaust vent pipes or right within the cabinet.

This video is of a 2" PVC furnace exhaust vent that was scoped, from the exterior vent termination, on a service call because of a no start/lockout condition. The abandoned yellow jacket nest was positioned at a critical bend which restricted airflow. Had the yellow jackets entered the intake vent, they could have nested right within the furnace cabinet, causing a much higher repair bill if it were an active nest. This repair, including the service call, scoping both vents and nest removal, was less than $300.