ADT Glass Break Sensor notifications are late, missing or excessive

The checks in more detail

Check that the phone allows notifications from the app and is not in a Focus mode. If you use text alerts, check the number is correct and that the carrier is not blocking messages from the short code. A glass break sensor that is in trouble sends a trouble signal rather than an alarm, and some accounts show trouble only on the panel. False alarms are a separate problem: a sensor near a speaker, a window rattling in wind, a loud bang from a dropped pan or a dog's bark can trigger it, and the cause is placement or sensitivity, which the installer can change.

Keep a log of when false alerts occur and what happened at that moment, since a pattern shows the cause. If alerts are late, the internet or the cellular link may be slow, and the monitoring center's signal may travel separately. If you never get any notification, even for a test, ask the monitoring company to check your contact settings. Test notifications whenever you change phone or number. Do not turn off alerts permanently to avoid false alarms; fix the cause. Make sure everyone who needs alerts, such as a second adult, is listed as a contact.

It helps to know that the sensor listens for two things in sequence, the low thud of an impact and the higher pitch of breaking glass, and it triggers when it hears both in a short time. A single loud noise rarely triggers it, so a test with a clap proves nothing and a test with the manufacturer's tester is the right check. If you get repeated alerts at the same time every day, look for a regular sound such as a delivery, a school bell or a garage door, and ask the installer whether the sensitivity can be lowered. Record what you hear and the time, which makes the pattern clear.