Looking for the best Zigbee or Zwave sensor that I can toss into a Fridge or Freezer and would report temperature with a battery life that can go more than a few weeks. I've been reading a few of the former posts on this topic which seem to reference sensors that are no longer available - so curious what people are using (based on current availability)?
The sensors I'm using in my fridge today seem to be working ok, but the Freezer sensors either die completely - or at least drain the battery way too fast.
In addition, where people have gotten a solution to work - what have been the settings you've used for frequency of reporting (both duration & temperature delta)?
To me, humditity is less of an issue for these, so ideally I'd disable that reporting or set it to a very long duration.
I started using the Xiaomi Aqara Temperature and Humidity Sensor WSDCGQ11LM - CR2032 but have recently started using Sonoff SNZB-02P - CR2477. You may notice I copied the device names where I have also identify the battery type. The CR2477 is substantially larger, so I hope they last longer. I was getting several months (maybe 6) with the Aqara. Both have humidity sensors. And just now I realized that neither are reporting their battery levels. Another thing to try to figure out!
You can just choose any device that reports temperature, whether it's a contact sensor or a motion sensor or a button etc., it doesn't really matter.
I have some old buttons {Iris V1, no longer available) in my refrigerators and freezers that report temperature, also have a leak sensor that went bad and stopped sensing leaks, but it still reports temperature so I use it for one of my freezers.
I haven't heard any significant battery drain out of the ordinary on any of them.
I fixed my battery issue. I didn't realize there was a built in driver for the Sonoffs. When they were discovered (I just added a one and verified it) they were selected as Generic Zigbee Temperature/Humidity Sensor, rather than the built in one. Maybe someone from @support_team can add this to the device list for the built-in driver Sonoff Zigbee Temperature/Humidity Sensor.
If you're going to use a sensitive sensor in a freezer, you have to make sure that there is no humidity condensation inside the sensor.
I have used scotch tape on the sensor itself to prevent this from happening, but your mileage may vary.
Condensation can be an issue. I have tried sealing the sensor in a ZipLock bag for moisture protection. You can add a desiccant packet if you have one available.
The YoLink Hub is the gateway device that connects all your YoLink devices to the Internet and to the user-friendly YoLink app.. It supports Ethernet and/or WiFi internet connectivity. The YoLink devices do not rely on WiFi, they instead communicate using the LoRa-based (long-range & low-power) wireless network generated by your Hub. The YoLink devices do not need WiFi, which may have a weak signal or may not be available where it is needed. Typical WiFi-based smart devices can bog down one's WiFi, creating traffic jams and poor performance, There is no monthly subscription fees with using any of the YoLink hubs and YoLink devices.
The 'YoLink Hub' provides the sensor data to Hubitat for automation routines.
I also have the YoLink water leak detectors and they work perfectly for my water heater, washer and water main areas of detection.
YoLink 3 (a 4G LTE Cellular Backup)
For those, who need sensors where there isn't any internet, YoLink makes a YoLink Hub 3. This hub is the third in YoLink's family of Hubs, the YoLink Hub 3 is the smart home gateway device that supports a 4G LTE Cellular Backup, ideal for remote & urban residences, and has a 1/4 mile extended range. The cellular subscription is $6.99 per Month, and automatically chooses AT&T, T-Mobile, and other major cellular data providers.
There are two big issues with placing any battery powered device in a freezer. First, the freezer case is nearly a Faraday cage, preventing wireless signals from passing through the walls of the freezer. The only way they can get out is through the seal around the doors. If you do go the battery powered route, you might want to put a repeater near the freezer.
The second issue is that batteries do not work well at temperatures below freezing, and especially at freezer temperatures which should be 0F/ minus 18C or even lower. Do not be surprised if the battery life indicator on the sensor drops to zero shortly after placing the device in the freezer.
From a sensor standpoint, it is best to keep the temperature sensor outside the freezer with a remove sensor on a thin cord passing through the door seal. I do have temperature readers that work in this manner, but they do not transmit to my Hubitat. I am still looking for the ideal device.
I agree with your statement for traditional indoor battery temperature sensors, but the YoLink temperature sensors and batteries work perfectly inside refrigerators and freezers at very low temperatures (Freezer temps below 0°F) and report accurate temperature and humidity for my use. YoLink sensors use a long-range radio frequency (LoRa) to send data to the Hub, allowing for wide coverage within a home.
Here are some of their features....
Environmental:
Operating Temperature Range: -22°F - 140°F (-30°C - 60°C)
Operating Humidity Range: ≤95% (non-condensing)
Other Features:
Temperature and humidity displayed on the YoLink app
LCD display shows current temperature (Celsius or Fahrenheit) and current humidity (%)
Extremely accurate temperature and humidity figures (+/- .3 degrees Celsius and +/- 3 percent humidity)
Self-calibration available via the YoLink app
Portable; may be placed anywhere in your home or wall-mounted
High/low temperature alerts
High/low humidity alerts
Historical temperature and humidity graphs displayed in hourly and daily figures
Wireless operation; no 120V outlet or wiring required
Battery-powered (two standard alkaline AAA batteries, included)
Up to 2 years of battery life, compared to 1 year for other brands
IFTTT, Home Assistant, Alexa (limited to voice queries of status) integration
YoLink’s industry-leading long range communication and low-power operation
Exceptional value; accurate temperature and humidity sensor in one smart device at a great price
Works with the convenient and user-friendly YoLink app
Know the current temperature and humidity level at the sensor’s location. Check remotely using the YoLink app, anytime and from anywhere
Create customized alerts, to be informed of high or low temperature and/or humidity levels via emails or phone notifications
Create custom automation using the YoLink app, to trigger responses from other YoLink devices, such as the Siren Alarm
Use the IFTTT service (www.ifttt.com) to create custom automation with YoLink and third-party devices, tailored to your particular needs and your IoT devices (IFTTT is a paid service for more than 3 custom automation)
Compact design allows for placing the sensor where others may not fit
Easy to install and portable; move to other locations as needed
Lower cost of ownership than other technologies; low-power operation means batteries may last over 2 years, compared to 1 or less from other brands
Carefree maintenance, with more years between battery replacement
Low-battery alerts give you advanced warning that it is almost time to replace the batteries
Uses standard alkaline batteries (2 AAA batteries); no Lithium or special batteries required
Extremely easy and fast installation using the YoLink app with Scan & Play
Here is one of my temperature sensors history in my Kitchen Freezer where the YoLink Hub is far away in the basement.
I suspect the humidity sensor is calibrated for typical house temperatures. I would not trust the humidity reading in a refrigerator. In a freezer, the humidity is essentially zero. Placing the sensor in a plastic bag would definitely render the humidity sensor useless.
I put a Third Reality Zigbee temp and humidity sensor in my kitchen and also in my garage refrigerator 3 months ago and they are working perfectly thus far. They paired up immediately and have not required any further intervention. After allowing them to acclimate overnight, their temperature needed calibrated by -7 degrees in the garage and -4 degrees in the kitchen, but I have found that every sensor I have tried in the refrigerator has needed some amount of calibration. They use 2 aaa batteries, so I anticipate them going quite a while between battery changes. I doubt that the humidity reading is accurate (one reading stays around 80% and the other 24%), but it’s not something that I am paying attention to for automations.
