Problem with 82-400

A quick learner from MD says:
July 24, 2023
The Atrium Lock 82-400 has become lazy (slow return of handles) AND the deadbolt is frozen. I have removed the screw that is supposed to secure the deadbolt, but am unable to remove the thumb knob. I am able to remove the lever handles using a proper-sized hex wrench but unfortunately the hex screw holding the thumb knob is of a smaller size. Is it necessary to remove the thumb knob (and its shaft) in order to remove the lock mechanism. Thank you!
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Casey from SWISCO responded:
July 25, 2023

Hello,

It is necessary to remove the key lock first since it goes through the mortise lock to the other side of the door. As long as the keylock is in place, you won't be able to remove the mortise. Thanks for posting and let us know if you need anything else. 
Brass Atrium Door Lever Lockset
Brass Atrium Door Lever Lockset
82-400
$101.70
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