There are a few reasons that this could be happening. To begin with, what happens if you try and use the key from outside or the thumbturn from the inside of your door? If you are unable to turn the thumbturn inside of your door then it is likely that the bolt itself is at fault and in need of replacement. If you can operate the deadbolt from the inside with the thumbturn but when you insert the key into the lock it will not turn then it is possible that the key has gone out of manufacturers specifications or the bottom pins inside of the lock are worn down. A possible remedy for you is to hire a Professional Locksmith to rekey your lock cylinder.
If you can turn the tumbturn inside of your door and the key from the outside of your door and both continually spin, it is very likely that the tailpiece is faulty and needs to be replaced.
If you have an older Schlage deadbolt on your door and you can work the deadbolt bolt from the inside using the thumbturn but when you insert the key, the key continually spins and does not work the deadbolt then it is likely that the tailpiece has fallen apart and requires replacement. The tailpiece that was originally supplied with the deadbolt has a washer at the end of it that is actually peaned onto the shaft of the tailpiece. This design was flawed and has lead to many of these tailpieces falling apart. Much later, Schlage introduced a single piece tailpiece.
Is your key hard to turn but the deadbolt works fine with the thumbturn from the inside of the door? The likely cause of that is a worn key or worn lock pins. You could hire a Locksmith to recombinate the lock and cut you new keys. This would bring the lock back up to manufacturers specifications. After this process the lock should work like a brand new lock. Your other option is to purchase a new lock and replace your faulty one. You would of course, need to know how the old lock comes apart and the new lock goes together. Remember that a trained Locksmith can supply and install a new lock for your door. A locksmith can also provide a better built lock like a Schlage B560 deadbolt that is not available at the big box retailers or hardware stores.
Security Article Written by: Toronto Locksmith
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