Hi,
I am using 2 ruuvi 4in1 in my camper : one for the fridge, one for the freezer.
The battery life time for the fridge is several months, that’s ok.
The battery life time for the freezer is few weeks only.
The temperature in the freezer is quite often below -20 ° C , sometimes down to -30°C
The operating temp for 4in1 is : -20 °C to +70 °C
For the ruuvi tag pro the operating temp is : -40 ºC to +85 ºC
Question :
Will the ruuvi tag pro‘s battery life last longer than the from ruuvi 4in1 ?
The short answer is that the battery life in RuuviTag Pro and RuuviTag will be somewhat identical in identical operating conditions.
The battery that is shipped with RuuviTag Pro (CR2477T) is capable for operating in extended temperature range and you can also use this battery for standard RuuviTag. In practise, I have had success with both RuuviTag versions and both battery types in both fridge and freezer.
The battery mileage may vary, depending on the conditions that your RuuviTag will be subjected to. Humidity can in some cases create resistance to the board which may effectively drain battery faster and this sounds like the case that you are experiencing with camper fridge. Keep the sensor close to the center of the fridge and avoid door, walls. You might also want to try to seal your RuuviTag into a ziplock bag to keep it from getting wet by potential spills or high humidity and see if it improves battery life.