make sure seals are good, (foam around manifold to blower or the filter housing) .
I also use a whirlpool airflow meter to test the customers vent, definitely an air flow problem, either the dryer or the vent hose in the wall.
They may need to call a vent cleaning company, I always check air flow when it comes to burnt thermal fuse, saves me recalls, absolves me from "you did not fix it right, doing same thing".
I show them the meter & tell them there is no warranty if they do not call to clean it.
- Samurai Appliance Repair Man likes this