Under normal usage the batteries in a Sensor Puck will last about a year. If a Sensor Puck is going through batteries quickly - over a few days - the Puck might be trying to do an OTA update, and killing the batteries because it doesn't have a strong WiFi connection.
WiFi uses a lot of power, which is why Gateway Pucks are required to be plugged in. Sensor Pucks aren't normally connected to WiFi, but will connect temporarily for an OTA update. (Sensor Pucks will also briefly connect to WiFi when downloading IR codes when paired with a mini split.)
- Try moving the Sensor Puck closer to your router
- Try plugging in the Sensor Puck using the supplied cable and adapter. This will provide more power during the update
- Ensure the batteries you're using are fresh
Note: Rechargeable batteries can sometimes result in false low battery alerts. When you do get these alerts, you can wait a few months before recharging.