Yes. When the sweep shows you the brush out of the pot you can be certain that the flue has been thoroughly swept from top to bottom.
IT IS NOT POSSIBLE TO SWEEP A CHIMNEY BY THE USE OF A VACUUM ONLY!
If a “sweep” does this and tells you he has swept your chimney, don’t pay him, show him the door, and if he claims to be a member of a trade body, report him.
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