AcuRite Digital Wireless Fridge and Freezer Thermometer with Alarm, Max/Min Temperature for Home and Restaurants (00515M) 4.25" x 3.75"

Easy to set up with great instructions. Accurate and easy to use. Would be better if it had a backlight but not a deal breaker. Great to glance at and see what my fridge/freezer temp is in the back of my canopy.

tl;dr version: This works fantastic for monitoring a standalone freezer in the basement. Full story: We have a standup refrigerator-sized freezer in our basement (mainly because that was the only place in the house we had room for it). We've managed to leave the door cracked open a total of 3 times now in about 10 years, due to simple negligence, and have lost hundreds of dollars in spoiled frozen foods as a result. There's no reason this needs to ever happen, so after the last time a month or so ago, one part of my fix was that I wanted something to sound an alarm if the temperature rises too much. Enter this simple wireless temperature sensor. Since the use case here is for a single-chamber freezer, and our fridge is well out of range 1 1/2 floors above on the other side of the house, I opted to just put both sensors inside the freezer. One is on the top shelf of the door, theoretically the highest temperature inside the freezer and the first location to start thawing if the door were left open. The other is buried deep on the bottom shelf near the back, which is theoretically the coldest area of the freezer. This way I get an idea of the effective range of temperatures throughout the freezer at any point in time. In case anyone's curious, there seems to be a fairly consistent 15F degree difference between the two sensor locations, plus or minus a few degrees. Installing the batteries and connecting the sensors to the display unit was quick and effortless. I didn't have any lithium batteries on hand, so despite the freezer being below the optimal range for alkalines, I went with what I had and gave it a shot, knowing I could just go pick up some lithiums the next day if it didn't work. So far the sensors haven't had any battery issues despite the subzero temperatures. Placing the sensors inside the freezer was also easy, although I couldn't make use of either the suction cups due to the low temperature or the wire shelf straps due to the shelves being thoroughly encased in frost and ice. That said, having them just sit on the shelves seems to work fine. The display unit is magnetically stuck to the front of the door and has had zero issue so far with the signal from the sensors punching through the metal frame. Both sensors show a very strong signal indicator. I have not had an opportunity yet to test the alarm feature. I did reprogram the "refrigerator" sensor's alarm range to freezer settings and turned on the alarm for both. As pointed out in the manual, while one sensor is labeled as fridge and one as freezer, they're otherwise identical and you can adjust the alarm range for each one independently. You're also not limited to just cold temperatures - the nominal max is 158F/70C although the display only goes up to 99.9 in Fahrenheit mode - so you could easily monitor something other than a fridge and/or freezer with this if you wanted to. Anyway, one of these days I should probably take one sensor out of the freezer for a while and let it warm up just to confirm that the alarm is audible from another room. Overall, I'm very happy with this purchase, especially considering the reasonable price.

I can't attest to the specific accuracy, that it's within x degrees and so on, but what I can attest to is that it's very easy to read and it's more than accurate enough for my uses. I also love that it shows the high and low over the last 24 hours. The reason I got them is that my fridge one day lost it's temperature and some food spoiled but not enough to be obvious. We almost got sick but luckily caught it on time. As a result we bought this to monitor the temperature and it's been a great piece of mind to be able to just look at them at random times and know that the last 24 hours the fridge has always been within a certain acceptable range. They have been running on batteries for months and they are doing great. That being said I would recommend using two thermometers (why I bought this item because it comes with two) so that they can be located in different parts of the fridge. Not only does it give you more confidence that they are working and accurate at first, but later on you can locate them in different areas such as the door which has a tendency to have a lower temperature if it's been left open and so on.

... the frustration of a fridge/freezer in the garage stopping working and not noticing until a few days later, I know the pain involved in having to throw out perfectly good (and expensive) food. So, I resolved to stop it happening again and I purchased these. Reviews that are written after time and not when in the initial haze of consumer contentment always carry far more weight, in my opinion, and this is one such as I have had these since November 2022. I am writing this now because, thanks to these beauties, I managed to head off another fodder fiasco when a different fridge/freezer in the garage suddenly stopped: I fixed the problem before I had to throw anything away because I became aware of the issue in good time. At last - something I bought that actually SAVED me money !! These are fairly straightforward to set up (although to set the warning alarms takes a little effort) and I am pleased to report that the batteries (two AAs in each) I installed in both sensors over a year ago - ALWAYS use lithium ones if you want a better experience ! - are still functioning just fine (although I have changed the three AAs in the receiver unit on one occasion). I decided not to keep the alarms as I didn't want any potential beeping in the middle of the night, so I simply verify the temperatures every day. It's actually quite fun to think that you are checking on the temperature of an appliance outside of the house ! There is an easy-to-see record of the previous 24-hour's minimum and maximum temperatures at the bottom of the screen and one push of a button shows you all the lowest and highest temperatures from when you last reset the unit. All numbers are clear to read. I do think that this set is quite expensive, though (and it was £60 when I purchased it), but one's choices are somewhat limited and at least I can show that they do work, so I guess it equates to value for money - especially when one compares it with a cost of replacing the contents of a well-stocked fridge/freezer !! I have the receiver unit on the side of a fridge in the kitchen (decent magnets present) and the actual sensors are about 20 feet away in the garden behind a metal garage door; I have had no issue with signal strength. And that's about it. As is my wont, I shall update this review if anything ceases to function as it should. If there is something specific that you would like to know that I have missed out, please ask a question and I shall do my best to respond... FV

Las lecturas son confiables, los compré para tener más control de los alimentos que almacenamos en el refrigerador, apesar de que nuestro refrigerador tiene un display digital para ajustar la temperatura, no confiaba en la precisión y quise tener un segundo monitor con estos sensores y las lecturas son muy parecidas aproximadamente +-2 grados. La opción de sujeción no es muy buena ya que se caían constantemente, opte por simplemente dejarlo en la charola del refrigerador sin tenerlo colgado en algún lugar en específico. Muy recomendados