The definition of a night latch is spring lock that can be opened from the outside with a key only and the inside by turning either a knob or short handle. This type of lock never needs to be locked with a key as just pulling the door closed will engage the latch into the strike plate.
The door is unlocked from the inside using the lever or unlocked from the outside using a key. Generally, night latches will come in two sizes. 60mm is commonly used for conventional doors, whereas those using glass panel doors will often choose a 40mm back set.
The first thing you can try for opening a jammed latch is to slide a plastic card (e.g. a credit card) between the door and the frame where the latch is located. This will hopefully force back the latch and the door will open.
A Night Latch (Yale Lock) is a lock commonly found on home front doors; they are mounted to doors that open inwards and mounted to the inner surface of the door. When the door is closed the night latch automatically latches the door shut.
A night latch (or night-latch or nightlatch) is lock that is fitted on the surface of a door; it is operated from the exterior side of the door by a key and from the interior (i.e. "secure") side of the door by a knob.
Lock does not respond – door is open and accessible.
Press each keypad button for response when pressed. Check batteries are installed and oriented correctly (polarity) in the battery case. Check batteries are in good condition; replace batteries* if discharged. Check to see if cable is fully connected and not pinched.
A night latch is a lock that can only be opened with a key from the outside and, as long as its not a double locking version, it can always be opened from the inside. The latch can be held open with the use of the snib or it can be locked closed with the snib stopping key operation from the outside.
Lock slipping indicates the slipping of the plastic between the door and the frame. The lock popping indicates the sound the latch/ lock makes when it's pushed in. Especially under pressure it can make a loud popping sound when the door opens.