What battery goes into a Honeywell 5811?

The Honeywell 5811 wireless door/window sensor uses a CR2032 3V Lithium battery. This is a coin cell battery, similar to those used in watches. Honeywell recommends using the Panasonic or Sener model CR2032 or the Duracell DL2032. There are other brands available, but these are recommended.

When your Honeywell wireless security system alerts you to a low battery on a zone programmed for your Honeywell 5811 wireless thin window or door sensor, you should replace the battery. If you do not change the battery, your Honeywell 5811 wireless thin door sensor will eventually stop working about (30) days after the initial low battery report. Before the battery dies completely you may experience RF supervision errors as the weakened battery can reduce the wireless range of the 5811 door/window transmitter. So, Alarm Grid suggests replacing the battery as soon as the low battery signal is detected.

The Honeywell 5811 uses a CR2032 3V lithium coin cell battery. Honeywell recommends using the CR2032 battery from Panasonic, Sener, or Duracell for this particular sensor. There are 2032 batteries available from other manufacturers, such as Renata, or Energizer, but since Honeywell either has not tested these other batteries, or they have and they simply do not recommend their use, Alarm Grid also does not recommend their use unless you simply can't find one of the recommended batteries as a replacement.

To replace the battery in your Honeywell 5811 wireless thin door or window sensor you will need a small flat head screwdriver. Insert the screwdriver into the notch along the short edge of the Honeywell 5811 and twist the blade gently to pry off the wireless transmitter from the backplate. Remove the old battery and install the new CR2032 3V lithium coin cell battery into the 5811 sensor. Be sure to observe proper polarity. When the new battery is inserted, the + symbol should be visible, as seen in the image below. Finally, hook the battery end of the 5811 onto the protruding plastic case tabs found along the opposite short edge of the Honeywell 5811 backplate and swing the wireless transmitter into place, snapping the sensor shut with firm pressure.

If your Honeywell L5100 LYNX Touch is being monitored by Alarm Grid, you should put your wireless security system on test with the monitoring station before replacing the battery in your Honeywell 5811 wireless window and door sensor. Once you have installed the new 3V lithium coin cell battery and verified that the sensor is working with the alarm panel, the 5811 wireless transmitter will automatically send a low battery restoral signal to clear the trouble on your LYNX Touch alarm control panel.