A humidity sensor measures the humidity of the environment. Many humidity sensors also measure temperature. They convert these measurements into an electronic signal that frequently can be downloaded or graphed. Humidity sensors come in a wide variety of sizes and functionalities.
Humidity sensors are useful in your home to make it sure is not too humid or dry. Humidity can aggravate asthma and can increase some toxic airborne chemicals. Dry air can affect your skin and eyes. A humidity sensor can help prevent both problems. Let’s find out about some of the more popular humidity sensors for the home.
Goabroa (12 Pack) Mini Hygrometer Thermometer
This is a set of 12 small, digital indoor sensors. Each has a humidity gauge monitor with a temperature meter sensor for Fahrenheit. They can quickly and easily let you know the temperature and humidity of your environment no matter where you are.
Each sensor is only 1.88 x 1.13 x 0.66 inches. The sensors are black and are made of ABS plastic. The built-in battery lasts up to 18 months.
Each sensor measures humidity and temperature via LCD display every 10 seconds with four sensitive vents which provide accurate readings each time. The humidity sensors are accurate to ±1% and has a range from 10% to 95% RH. The temperature range is -50 to +158 degrees Fahrenheit and measures in 0.1 degree intervals.
The mini size is very versatile. Try using them in all the usual places in your home as well as your reptile tank, guitar case, cigar humidor, or any small space.
One drawback is, this device should not be placed directly on a heat or humidification source. Also, the sensors cannot be calibrated and the temperature settings cannot be changed to Celsius. Some users do not find the humidity sensor sensitive enough.
Features
- Set of 12 mini digital indoor humidity/temperature sensors on LCD display
- Updates humidity and temperature readings every 10 seconds
- Humidity sensors accurate to ±1% with range of 10% to 95%
- Temperature range -50 to +150 degrees Fahrenheit in 0.1 degree intervals
- Built in battery lasts up to 18 months
Govee Bluetooth Hygrometer Thermometer
This smart sensor works with Bluetooth to provide a humidity and temperature gauge with remote monitor. It measures temperature to 0.5 degree Fahrenheit accuracy, and humidity to ±3% RH. It refreshes the measurements every two seconds.
It comes in black or grey and is made of plastic, with a large three inch LCD display. The numbers are large and easy to read. The sensor requires two triple A batteries, which are included.
The sensor range is up to 196 feet, which can cover an entire home.
It comes with a notification alert. If your temperature or humidity reaches the preprogrammed maximum or minimum limits, the sensor will notify you. This is a handy feature if you are using the sensor for your wine cellar or greenhouse. The sensor also comes with three level comfort indicators (dry, comfort, wet) that you can preprogram.
It comes with 20 days of online data storage. The sensor can graph your temperature and humidity readings over time. And you can export two years of data to CVS format.
Features
- Smart sensor works with Bluetooth and remote monitor; 196 foot sensor range
- Measures temperature to 0.5 degree Fahrenheit accuracy
- Measures humidity to ±3% RH
- Refreshes measurements every two seconds
- Notification alert if humidity or temperature reach preprogrammed limits
- 20 days online data storage; two years data conversion to CVS
Inkbird Wireless Thermometer Humidity and Temperature Monitor
This wireless humidity and temperature monitor works with Bluetooth technology and has an app for Android and iOS. It is freezer safe and has a wide range of -40 to +140 degrees Fahrenheit and 0% to 99% for humidity. If you wish, you can switch the temperature settings to Celsius.
This sensor has a range of up to 98 feet. It also has a built in magnet so you can easily attach it to metal. The sensor is waterproof, which also makes it perfect for the freezer and fridge. It is not safe to use permanently underwater though, so is not suitable for a fish tank.
The sensor accurately graphs the temperature and humidity readings over time. You can also program maximum and minimum temperature and be notified if the readings get out of range. You can adjust the sampling interval. And all this can be done through the app. The sensor is high accuracy and can be calibrated. It can store up to 30,000 points of data.
This device requires two triple A batteries which will last for up to six months. The batteries are not included.
Features
- Sensor works with Bluetooth, with apps for Android and iOS; senses up to 98 feet
- Freezer safe; wide temperature range -40 to +140 degrees Fahrenheit
- Humidity range 0% to 99%; waterproof
- Accurately graphs temperature and humidity readings over time
- Max and min temperature can be preprogrammed, and notifies if out of range
- Built-in magnet for easy attachment to metal
MOCREO Upgraded Indoor Thermometer Hygrometer
This package of three sensors can monitor your temperature and humidity remotely through an app. You can buy more sensors for the hub that comes in this package. One hub can manage up to 16 sensors. The range of each sensor is up to 49 feet.
Each sensor is reliable and long lasting. It measures temperature and humidity every three seconds, with a temperature reading accuracy of ±0.5 degrees Fahrenheit and humidity accuracy of ±0.3% RH. You can set your desired temperature and humidity conditions and the app will alert you if the readings are outside the preset range. The temperature can be set anywhere between -4 to +140 degrees Fahrenheit and you can easily switch to Celsius if desired.
It has up to two years of data storage and can graph out the results for you. It is powered by three lithium batteries that are included, and they last more than two years.
Features
- Set of three sensors and central hub with range up to 49 feet
- Measures temperature and humidity every three seconds
- Temperature accuracy ±5 degrees Fahrenheit and humidity accuracy of 0.3% RH
- Temperature range -4 to +140 degrees Fahrenheit
- Has up to two years of data storage and can graph out the results
- Powered by three lithium batteries lasting more than two years
SensorPush Wireless Thermometer/Hygrometer for iPhone/Android
This wireless temperature/humidity sensor can work with both iPhone and Android. It has a very long range of 325 feet and has an easy, one-time setup using the beautifully designed, free app. It can push your temperature and humidity readings to your phone via Bluetooth.
One phone can monitor an unlimited number of sensors and vice versa – one sensor can be monitored by an unlimited number of phones.
The temperature range is -40 to +140 degrees Fahrenheit and the humidity range is 0% to 100%. The temperature accuracy is ±0.9 degrees Fahrenheit and humidity accuracy is ±3%.
This sensor provides minute-by-minute updates and will graph your readings and/or export to CVS if you wish. It automatically maintains the last 20 days of data on the device.
You can add another device, sold separately, called the G1 WiFi Gateway, to save data and issue alerts over the internet.
The battery life is typically over one year.
Features
- Wireless temperature/humidity sensor works with both iPhone and Android
- Long range, up to 325 feet
- Pushes temperature and humidity readings to phone via Bluetooth
- Provides minute-by-minute updates
- Graphs readings and can export to CVS
- Automatically maintains last 20 days of data
SwitchBot Smart Hygrometer Thermometer
This wireless humidity/temperature sensor works with Bluetooth and incorporates app alerts. It is compatible with Alexa, Google Home, HomePod, and IFTTT. It can send you alerts from anywhere that is near a Bluetooth.
It monitors the environment accurately, all day, every day. The resolution is ±0.1 degrees Fahrenheit for temperature and ±1% for humidity. The temperature range is -4 to +176 degrees Fahrenheit and humidity range is 0% to 99%. The sensor range is 394 feet.
You can set it up for home automation, for example, to turn your air conditioner on and off as needed.
The app will graph your data concisely with daily, weekly, or monthly filters to track changes in your humidity or temperature. The sensor automatically maintains the most recent 36 days of data, and unlimited data can be stored on the cloud and exported as you wish.
You can set alerts for when the temperature or humidity goes beyond your preset limits.
It has a clear, high resolution LED screen for easy viewing.
It sets up in seconds. It has a magnetic back and 3M metal plate which enable you to place the sensor anywhere. It also stands upright for tabletop use.
Features
- Humidity/temperature sensor works with Bluetooth and app alerts
- Resolution is ±1 degrees Fahrenheit for temperature, and ±1% for humidity
- Sensor range is 394 feet
- Temperature range is -4 to +176 degrees Fahrenheit and humidity range is 0% to 99%
- Graphs data with daily, weekly, or monthly filters
- Maintains 36 days of data, and unlimited data can be stored and exported
Applications of humidity sensors
Humidity sensors have many different uses. People with illnesses caused or affected by humidity often use humidity sensors. These sensors are also found as part of home heating, ventilating, and air conditioning (HVAC) systems.
These sensors are also used in cars, humidors, greenhouses, offices, and meteorology stations. Many industries, such as those creating textiles, use humidity indicators. In this case, humidity affects properties of the fabric such as friction, fiber diameter, strength, and elasticity. Cotton, wool, and silk require different humidity levels.
How to choose a humidity sensor
There are many things you should consider before purchasing a humidity sensor. Here are a few.
RH range
If you know the RH (relative humidity) range you need to be measuring for, choose a humidity sensor that measures within that range. Or choose one that has a very wide RH, such as 0% to 99% RH.
Accuracy of humidity measurement
Determine how accurate you need your humidity sensor to be. For some uses, you may want high accuracy. If you are just adjusting humidity in your home, you might not require super high accuracy.
Temperature range
Some people use these sensors in a freezer and others in a hot environment. If your humidity sensor has a temperature sensor, make sure it has a range that will fit your requirements.
Calibration
If you can, check how the manufacturer calibrates the sensor. Some manufacturers perform manual calibrations at only three RH values – high 80%, medium 50%, and low 30%. Others are digitally calibrated at eight or more RH values against standards determined by the National Institute of Standards and Technology (NIST).
Also check if the sensor can be easily recalibrated.
By considering the reasons you need a humidity sensor, the considerations you need to make, and comparing the various brands on the market, you are sure to find the sensor that works best for your needs.
Photo credit: Jerome Quek/Shutterstock