I rarely throw a BVC coil away. Here is my method.
If I suspect a coil problem, I replace it and throw the old one in a glass jar. The problem is solved but that does't mean that coil was bad.
When I get 4-5 BVCs in the jar, I agitate them thoroughly with Everclear (grain alcohol), let soak for 10-15 min, agitate again, remove and let dry.
After that, I have over a 90% success rate reusing those washed coils as if they were new.