How to Disable a Window Sensor on a House Alarm

If you have window alarms, you have to be able to disable them, or you can't open the windows without setting off the alarm and creating a lot of noise in the house. If your house is wired into a security network, trying to get a little air in the house could even earn you a visit from a security official or the police.

Depending on which type of sensor you have, you may be able to disable it manually, but the safest way to disable any type of security sensor is to temporarily bypass its zone in the security system's control panel. The problem with the second method is that the bypass will be lost if you rearm the system, and the alarm will go off. If you need to keep the window open for a while, it's best to bypass the zone permanently and reprogram it when you finally do close the window.

The moveable part of a magnetic sensor, which is the part attached to the window, looks like a rectangular plastic pill box with no visible buttons or other mechanisms. When the magnetic attraction between the moveable part and the stationary part attached to the window frame — which is the part wired into the network — is disturbed, the alarm sounds. You may be able to trick the sensor by using a kitchen magnet.

To do this, you have to hold the magnet as close to the stationary sensor as possible. This means you have to open the window to expose the sensor, so if you don't turn off the system, the alarm may sound momentarily. Once the window is open, you can tape the magnet to the sensor. You can even remove the movable part of the sensor from the window and attach it to the window frame to fool the sensor into thinking the window is still closed.

Button-type sensors have a visible button that is depressed by a probe attached to the window, and when you open the window, the probe releases the button, and the alarm sounds. This type of alarm is easier to disable than a magnetic sensor because all you have to do is hold down the button while you open the window and then use something to keep the button depressed. Tape won't work by itself, but if you put a small, hard object on the tape and secure the tape so that the object is pushing against the button, that should work.

When the time comes to close the window, you'll have to release the button momentarily, so make sure the alarm is off. Once the probe on the window fully depresses the button, it's safe to turn the alarm back on.

The method you use to bypass a zone on your central control board varies, depending on the home security system, so consult the owner's manual for your system to get the specific instructions. If other windows are included on the zone, they will be disabled as well. If you disable the zone temporarily, you can reactivate it by rearming the system. If you disable the zone permanently so you can keep the window open, follow the manufacturer's instructions for reprogramming that zone back into the system when you want to reactivate the alarm.