An emergency/dual action cylinder, is a cylinder that can be turned by a key on the outside of the door, and the inside of the door at the same time. You can easily test if your cylinder supports this by doing the following:
- With the door open, insert a key into the lock on the outside face of the door and the inside face of the door at the same time.
- While gripping both keys, try to turn them
- If both keys move at the same time, and the lock on the door opens and closes, your cylinder has emergency action functionality
Having emergency action functionality is important for the Yale Linus®Smart Lock, as for a Euro profile cylinder, it grips onto the key on the inside of the door. Therefore if you don’t have a cylinder with emergency action functionality, we would advise changing the cylinder to one with this feature as otherwise you will have no mechanical override on the outside of your door. To find a cylinder with this feature please visit www.yalehome.com and look for the “Works with Linus®” badge for a compatible cylinder with this feature.

Some cylinders have a thumbturn on the inside of the door, this allows the door to be locked by the thumbturn instead of having to use a key.
As thumbturn's come in all shapes and sizes, it is again not possible for the Linus® Smart Lock to be fitted over the top of a cylinder. Therefore if your cylinder has a thumbturn on the inside of your door, you will need to change the cylinder to a compatible version.
To find a compatible cylinder, Please visit www.yalehome.comand look for the “Works with Linus(R)” badge for a compatible cylinder.
