Connecting the app to your fridge, and what to do when something looks wrong.
Then the hard part is done: the Pi, the Zigbee stick and the sensor were set up and tested before it reached you. You need to do three things.
Power for the Pi, and the sensor inside the fridge — high up, near the door seal rather than buried behind bottles. Give it a couple of minutes.
Install Cava Guard, then enter the address and access token that came with the box. Tap Test connection before saving: it tells you separately whether the address is wrong or the token is, which are the two mistakes people actually make.
Open the sensor and set the temperature range you want to be warned about. Nothing is set for you on purpose — a range inherited from somebody else's fridge would alarm on your first evening. Silence and battery are watched from the moment a sensor appears, so nothing is ever fully unmonitored.
Out of the box the app talks to the Pi on your home network. For it to work when you are away, open Settings → Remote access and follow the sign-in. That puts your Pi on your own private Tailscale network, which is free for personal use. Nothing is exposed to the internet and no ports are opened on your router.
| "Can't reach the Pi" | At home: check the Pi has power and your phone is on the same Wi-Fi. Away: remote access needs to have been turned on once, from home. |
|---|---|
| The token was rejected | The address is right and the server answered, but the token is wrong. Re-enter it from the card that came with the box. |
| A sensor has gone quiet | Usually the battery, sometimes the distance. The sensor detail screen shows both the battery level and the signal strength. |
| Alerts arrive late, or silently | Check that notifications are allowed for Cava Guard in iOS Settings. Temperature alarms are sent time-sensitive so they break through Focus, but they cannot break through being switched off. |
| Everything looks fine but nothing updates | The dashboard shows when each reading arrived. If the whole system is stale rather than one sensor, restart the Pi. |
Cava Guard talks to a small open server — a Raspberry Pi running a Zigbee coordinator and a monitoring service. It is not yet packaged for general release. If you want to build one, get in touch and we will point you at what you need.
support@cavaguard.com — a real person, usually within a few days.
← Cava Guard