Showing Both Fridge and Freezer Ruuvi Tag Temps on the Victron GUIv2 Overview Page
Getting Both Fridge and Freezer on the GUIv2 Overview at Once
The Venus OS GUIv2 overview page has space for a single temperature reading front-and-centre. One Ruuvi tag works great. Two — fridge and freezer — and you’re stuck picking one. The community workaround that most people land on is GuiMods, a set of patches for Venus OS that extends the overview to show multiple temperature tiles without having to dig through submenus every time you want to check the other sensor.
Why GUIv2 Only Shows One by Default
Venus OS exposes each Bluetooth temperature sensor as a separate service on the dBus system bus. GUIv2 reads whichever is set as the primary and renders it on the overview. Nothing in the stock UI lets you add a second. That’s a deliberate simplicity choice, not an oversight — but it’s frustrating when you genuinely need both readings.
GuiMods changes this by patching GUIv2 to query all temperature services on dBus and make them selectable for the overview layout.
Installing GuiMods
GuiMods is installed over SSH on a Cerbo GX or a Raspberry Pi running Venus OS. The installer script handles most of it. A few things to know before you start:
- Take a snapshot or note your current Venus OS version. GuiMods releases are tied to specific Venus OS versions — installing a mismatched release can break the UI.
- The mod survives firmware updates on Cerbo GX if you re-run the installer afterwards. It does not persist automatically.
- SSH access needs to be enabled in Venus OS settings first (Device List → Cerbo GX → SSH on LAN).
Once installed, your Ruuvi tags appear as configurable tiles. You assign them to positions on the overview from the GuiMods settings page inside Venus OS.
Layout Options for Two Temperatures
The OP raised three layout ideas. All three exist in some form in GuiMods:
- Stacked vertically — two readings one above the other in the centre of the overview. Legible from across a van or cabin, and the most common choice.
- Smaller font, side by side — fits both values in the same footprint as one, but gets hard to read at distance. Fine for a dash-mounted screen you sit close to.
- Mapped to a ring slot — if you have an unused ring (say, you don’t use tank monitoring), GuiMods can assign a temperature sensor to it. This is probably the cleanest solution visually, and it’s the layout that looks most like it belongs in the stock UI.
Availability of each layout depends on your Venus OS version and the GuiMods release. Check the release notes on the GuiMods GitHub before assuming a specific option is there.
Ruuvi Tag Specs and the Freezer Caveat
The stock RuuviTag runs a CR2477 coin cell. Ruuvi rates that combination to -20°C at the low end. A typical household freezer targets around -18°C — right at the edge. In a vehicle freezer that’s been sitting in cold overnight, you can push past that limit.
Ruuvi offers a CR2477T wide-temperature battery that extends the lower operating limit to -40°C, matching the electronics’ actual capability. If your freezer runs cold or the sensor itself sits in a cold environment, this is an easy swap and it matters. Accuracy is ±0.2°C in the 5–60°C band; below that range accuracy degrades, but for typical fridge and freezer monitoring it’s still perfectly usable.
One other thing worth knowing: IP67 rating means the tag handles condensation and brief submersion, so mounting inside a fridge is fine. Just make sure Bluetooth can still reach your Cerbo or adapter through the door seal.
Bluetooth Reliability on the Cerbo GX
The built-in Bluetooth radio on the Cerbo GX has a known reliability issue with Ruuvi tags. Victron flagged this in the Venus OS v2.80 release notes when Ruuvi support was first introduced. The recommended fix is a USB Bluetooth adapter. A short USB extension cable to move the adapter away from the Cerbo’s own electronics helps further. Drop-outs that seem like a Ruuvi problem are often actually a radio problem.
If GuiMods Isn’t for You
There’s a lower-maintenance alternative: the dbus-mqtt bridge, which publishes Venus OS data including temperature readings to an MQTT broker. From there you can pull both sensors into Node-RED, Home Assistant, or a Grafana panel on a separate small screen. More setup work upfront, but the display isn’t dependent on a community mod keeping pace with Venus OS releases. For a simple two-sensor fridge/freezer situation, GuiMods is usually the faster path.
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