Refrigerators, or fridges as they are more commonly known, are one of the most important inventions of the 20th century. With these cold cabinets, we can preserve food from days to several weeks with ease. Also, we need to worry far less about all sorts of illnesses caused by spoiled foods. Luckily, remote fridge temperature monitoring is available for everyone nowadays!
Most of us consider fridges to always be in the correct conditions for our food, which is most certainly not the case!
In this article, we will discuss what will happen to your food if your fridge is not running at the correct temperature. Or at least if something is not working as well as it should. Additionally, we are going to look at ways to measure and control your fridge’s temperature and humidity. In the end, I will give you some useful tips regarding food storage inside a fridge.
What is the best temperature in a fridge?
A fridge’s temperature should be around 2 °C – 5 °C at all times according to the FDA. Most foodstuffs are safe in these temperatures. The exception is with meat or fish products, which you must keep at a temperature below 3 °C as they spoil rather quickly. Most fridges have different temperature areas inside them, which helps to store different kinds of foodstuffs. More about this later.
Most fridges run above the threshold temperature of 5 °C, especially during summers when the ambient air is warm and the fridge is opened constantly.
What will happen if the temperature of a fridge is too high?
If the temperature is above 5 °C, bacteria will start to grow much faster. Fridge’s main idea is to cool the foodstuffs so that bacteria can not grow on it. In temperatures above 5 °C these bacteria are growing exponentially faster compared to temperatures below 5 °C.
Not all bacteria are harmful to people, but you should still try to reduce their numbers on your food. Most common bacteria that may cause food poisoning are Salmonella and E. Coli.
Also, food will remain fresh for longer if kept in colder temperatures.
Measuring fridge humidity – Is it necessary?
Correct air humidity is not as important as correct temperature inside a fridge, but excess moisture could lead to frost building up on the fridge’s inner walls. This frost can lead to other problems inside the fridge such as issues with cooling and excessive energy consumption.
Fresh foods such as vegetables and fruits like to stay in a more humid environment than other groceries. That is why most fridges have vegetable and fruit boxes on the bottom. Their aim is to capture these vegetables’ moisture inside the box to keep them in a nice humid environment.
It is still good to know your fridge’s moisture levels if you, for example, have frost building up quickly on the back-side of the fridge.
How to measure fridge temperature
Fridges temperatures may fluctuate much as the door is being opened and the cooling is working. This is why an analogue thermometer is not the most reliable device, as you cannot know the temperature at all times. Also, as mentioned before, the temperatures inside the fridge vary according to the location. Generally, the back of the fridge is colder than the door and the front.
Luckily, there are smart, wireless sensors that can measure the conditions constantly and transfer these readings seamlessly to your mobile phone. Bluetooth fridge thermometers are superior compared to older analogue thermometers.
- Purchase a high-quality thermometer.
Make sure you can read the thermometer when the door is closed. The temperature fluctuates as the door is opened and closed.
- Place the thermometer carefully in the fridge.
The temperatures inside the fridge vary according to the location. Generally, the back of the fridge is colder than the door and the front.
- Set alerts for the thermometer
Set alerts to make sure the temperature stays at the correct levels
- Keep right temperature
Keep the fridge temperature at or around 40° F (4° C)
Bluetooth fridge monitor at its finest
One of the best sensors on the market currently is the RuuviTag. It is small, works with Bluetooth and has a convenient mobile application. This application, RuuviStation, can be turned into a Bluetooth fridge thermometer iphone or android app in no time. In addition to being a Bluetooth fridge temperature sensor, RuuviTag also measures air humidity, air pressure, as well as movement inside the fridge making it an all around fridge monitoring system.
The RuuviTag also has the function to alert you if a measurement falls outside the preferred parameters. For example, you can set the sensor to alert you if the temperature inside your fridge reaches above 5 °C and you can instantly inspect what could be causing this and set the thermostat to correct levels.
Usually, thermostats in fridges cannot be set to exact temperatures, but rather have a scale of 1 to 5. That is why it is important to measure the real temperature inside the fridge so that you can adjust the thermostat correctly. More modern fridges have digital thermostats that allow you to set the target temperature you want, but even then it is useful to measure the actual temperature inside your fridge.
You can also find out the differences between the temperatures in different areas inside the fridge. The RuuviStation app displays easy-to-read graphs so you can easily compare these differences.
Other similar sensors currently on the market are Netatmo’s and Govee’s environmental sensors which measure temperature and humidity values.
Monitoring fridge temperature at all times with Ruuvi Gateway
RuuviTags work with the RuuviGateway, which is a router designed to allow you to monitor environmental conditions remotely. RuuviGateway receives RuuviTags’ data via Bluetooth. Then, it uploads the measurement data into the Ruuvi Cloud service. RuuviGateway can support multiple sensors at the same time. RuuviGateway transforms RuuviTags into remote fridge thermometers and gives you the power to check on your fridge’s conditions when you are not at home.
Automating fridge temperature checks
As mentioned earlier, the RuuviStation app can alert you if conditions are not optimal. This function is also available with the RuuviGateway as well! If you link your fridge’s RuuviTag to your RuuviGateway, you will have a fridge temperature alarm system that works via WiFi. Read more about Ruuvi Gateway here.
This could be used, for example, to monitor your fridge during a vacation. If your fridge breaks down, you will be notified as the temperature rises. You can then ask your relatives/friends to check the situation before the fridge could cause any electrical or water related problems to your house. A WiFi fridge thermometer in the form of a RuuviTag is a cheap way to prevent more expensive problems in your house.
Using fridge temperature tracking to find out the differences in temperatures inside a fridge
I kept my RuuviTag in my fridge and switched its location from the back of the fridge to the door of the fridge. The temperature measurement is in the top graph. Here we can see the measurement data for three consecutive days.
As you can see, my fridge is a bit too warm. Although, the back of my fridge remains at correct temperatures at all times. When the temperature reaches 6 °C, it drops to 2 °C fairly quickly.
Can you tell when I moved the RuuviTag to the front of the fridge? Or when I placed warm soup in the fridge?
As you can see, the temperature in the door is nowhere near the required temperature for dairy products, for example. This is why it is so important not to keep dairy products in the door!
Useful tips for storing food in a fridge
As mentioned above, meat and fish products need special attention in storing. Also, even when kept in low temperatures, they cannot be stored for a longer period of time. Dairy products are also a good medium for bacteria to grow on. They should be kept in the colder parts of the fridge. This means that they should not be in the fridge door, as it is one the warmest places inside a fridge!
Vegetables and fruits should be kept in the boxes inside the fridge. Typically, the air inside the fridge is dry, as the air is constantly cooled down. That is why they should always be in these boxes so they can remain fresh for longer. Keep in mind to not place fruits right next to vegetables as most fruits contain ethylene which helps them to ripen faster. If fruits are stored with vegetables, ethylene will also cause the vegetables to ripen sooner than you have planned.
The top shelf should be left for leftovers as its temperature is usually the most stable.
The fridge door should be for foods with preservatives in them. As the door opens, outside air will warm up the door area immediately.
As great an invention as a fridge is, it is not the foolproof tool for food storage. By paying attention to your fridge’s temperature, you can avoid food diseases such as Salmonella. With correct temperatures you can also store food for longer periods of time and prevent unnecessary food waste. Food waste is a big problem in our modern society and reducing it is good for our planet.
Smart sensors give you the possibility to scrutinise your fridge’s conditions round the clock.
Would you like to have one?
RuuviTag is a smart sensor that can be used to save your food from spoiling. Thanks to its large functioning range, it can be used to ensure your food’s well-being in both the fridge and freezer, or even in an oven if you like to dry your food for future consumption.
What is the correct temperature inside a fridge?
According to the FDA, correct temperature in a fridge is between 2 °C and 6 °C.
What problems stem from a fridge that is too warm?
Food will spoil quickly in a warm fridge as the bacteria grow faster than in a colder fridge.
How will you know if your fridge is too cold?
You can measure your fridge’s temperature easily by using inexpensive smart temperature sensors such as RuuviTag.
How to measure fridge temperature in general?
Inexpensive smart sensors, such as RuuviTag, are by far the most convenient and reliable way to measure fridge temperature.
Do I need a fridge humidity sensor?
A fridge humidity sensor is useful but not necessary. Too moist fridges can cause the back of the fridge to freeze quickly which will harm the fridges thermostat. By keeping an eye on the optimal humidity level, you can save energy. Most convenient way to measure frigde’s humidity is by using a thermometer which is equipped with a humidity sensor.
How to use Ruuvi as a fridge temperature monitor?
Place a RuuviTag inside your fridge in a desired place. Then you can just simply download the Ruuvi Station application and start monitoring right away. If you have multiple fridges, you can place a RuuviTag in all of them and monitor them at the same time. You can also set alerts to different parameters and the application tells you exactly which fridge is not functioning properly.