Wireless Temperature and Humidity Sensor - Developed in The USA - 24/7 Data Logger with Alarm – Bluetooth Smart Thermometer and Hygrometer - Bluetooth Only - Not WiFi

This is a great product, and does exactly what it promised. The price is currently a little bit steep (~$40) per unit when compared to others, but you get back a well working and useful device. The Bluetooth range is incredible, even with the signal blocked by stainless steel doors.The reason for this purchase was a kitchen refrigerator and freezer combo that appeared not to cool well, or at least very inconsistent. Before purchasing two of these units, we cleaned out the coils located under the combo that were full of dust. First with a coil brush to get the biggest dust bunnies out, then a final clean with a battery powered little leaf blower (Makita). The leaf blower did the trick and made everything look like new. This required unplugging the combo and removal of back plate to make compressor area accessible for cleanout.Moving on from cleaning the combo, I reviewed multiple solutions of how to monitor temperature in both refrigerator and freezer compartments. First I was set on some high grade mechanical temperature meters, but after thinking about it for a little longer I didn't want to have to open and close the doors all the time in order to see what the temperature was. Also, the temperature is always moving down when the compressor is running, and up when it is not. The refrigerator and freezer operate in a bandwidth, and when it is equipped with auto-defrost you might think the freezer is not working while it is just cycling through a defrost cycle.Then the sensor itself; I'm tech savvy due to my profession as an engineer, so I typically try to buy quality over quantity. First thing I did was checking it's accuracy with some lab grade equipment, and readings were well within 35% of the maximum allowable tolerances (see specs). These units can easily be calibrated via the app, which I did, although they would have been fine without these minor adjustments.The app is easy to use, and has hourly, daily, weekly, monthly and yearly graphs that show min/max and average for selected time range. There is an option to download all data points to a computer or your phone. Very useful to see performance over time, and whether or not it is time to clean the coils. With an auto-defrost feature, you'll be able to tell exactly how many times it runs this feature. If it starts happening more often, you may have door seals that are worn, or usage might have been going up (open door more often, and this cycle runs more often. It was a surprise seeing the freezer go up to 41°F about once a day.That gets me to one point of improvement I would like to see in the app; there needs to be a delay that can be set before it warns you when temperature reaches a certain level for a determined time. For instance, I set my freezer alarm at 9°F. I want the app to notify me only when the temperature is above this temperature for more than 2 hours. Currently, I get notifications every time the auto-defrost cycle is running, which leaves temperatures above 9°F for a little over an hour. For this reason I had to remove the alarm, or basically set it at over 44°F, which now will not warn me anymore if freezer contents are over 9°F for an extended amount of time.Last thing I would like to mention is that you'll need to give the app continue location access, which is only related to Bluetooth access. You can turn it off to allow only when you open the app, but it would then not give you an alarm anymore unless you open the app. Without alarms set you could just give access only when the app is open.This item is definitely a winner, but I still hope Tempi.Fi will add a delayed alarm feature to their app so it can be used in refrigerators or freezers with auto-defrost function, or to limit alarms when loading groceries. It comes with double sided 3M tape, but instead I used "3M Dual Lock" velcro so I easily can take the units out when replacing batteries (they should last 1 year). Perhaps another improvement idea. I hope their will be a gateway soon, as they state they are working on it, and it would allow for temperature checks wherever you are.

I hang deer in a refrigerated walk-in inside a storage building approximately 150 ft from my home. I was so tired of having to walk out to monitor the temp to ensure the meat was aging correctly and not spoiling. This thermometer was extremely easy to set up and has been working flawlessly for the last couple weeks. Unfortunately the range is more limited when the signal has to go through the insulated wall of the cooler, the storage building wall and the wall of my home so I have to be in the nearest corner of my house to the storage building. But honestly it is a minimal inconvenience. This thing is really great. Very accurate, and instantly updates when in range.

Having something be Bluetooth based in your fridge is flat out lame I suppose maybe there’s some way of connecting the Bluetooth to some kind of Bluetooth hub and then having that connect to your Wi-Fi and routing or something but basically I just connected this to my phone and my fridge is too far away from my phone so I really couldn’t use it for any good alerting. That said it does have an awesome app and essentially when you go to the fridge, you can get the full history minute by minute or hour by hour or whatever it is and all through the night and so you can see when it’s getting cold or hot and all that and max and minimum temperatures. I got it so I could store medicine and not have the medicine go bad. I was amazed by how much the temperature actually fluctuates in my fridge just with all the people opened it during the day and then how freaking cold it gets at night so it did the job. It wasn’t that expensive it can broadcast right through a medicine box and outside of the fridge has a real nice interface downside is the Bluetooth doesn’t really go that far , so is it if you wanted to use it for a real time alert unless you’re using some kind of special hub you would have to be in the same room. I never bother to look it up probably there is some kind of special hub that would relay this. Let me google on Amazon here…