Here’s What You Need To Know About Infrared Thermometer

Infrared Thermometer

Learn everything about infrared thermometers!

When you think of a thermometer, you typically envision a gadget with a probe inserted into the thing to get measurements. Probe-style thermometers have long been a standard, whether it's a thermometer under your tongue to take your temperature or a food thermometer that you push into a piece of meat to check if it's done. However, there are various alternative options today, with an infrared thermometer being one of the most intriguing and useful. An infrared alternative has a lot to offer regarding simplicity of use and reliable readings.

Infrared thermometers are useful for monitoring temperature. It's used when thermocouples or other probe type sensors are unavailable or don't provide correct data. The monitored object is either moving, surrounded by an EM field, as in induction heating. You may also enclose it in a vacuum or other controlled atmosphere. Some also use it in applications that need a quick reaction.

Suppose you used a laser to help aim the thermometer. In that case, we can also call it a laser thermometer, non-contact thermometer or temperature gun. It refers to the device's capacity to monitor temperature from a distance.



When you need to determine the surface temperature of an object, it may require an infrared thermometer. The infrared beam only bounces off the surface. That's why it's not a good measurement method for determining internal temperature. There are practically endless possibilities for this technology, and it is already in use in various industries. Checking the amount of heat emitted by a piece of equipment, for example, is a useful approach to looking for potential problems on the inside. There's a good possibility that something is wrong internally if the equipment is hotter than it should be on the surface. 

It's easy to see why infrared thermometers are popular in various industries like HVAC. Imagine how many different kinds are available today and how accurate they've gotten.


While the technology that allows these thermometers to function is sophisticated, the notion is straightforward. Everything with mass produces some energy, which expels in heat. Because all objects radiate heat, an infrared thermometer can detect the object's surface temperature. It does this by measuring the difference between the IR rays emitted by the object and those emitted by the surrounding environment.

An infrared thermometer is the best and quickest method to get a temperature reading in various situations because you get the reading in seconds. The IR thermometer works by focussing IR rays from the object and funnelling them into a detector, also known as a thermopile. The IR radiation then converts to heat in the thermopile, converted to electricity, then measured. The amount of electricity generated by the rays emitted by the object in issue ultimately determines the temperature indicated on the thermometer.


While a thermometer isn't a fascinating piece of equipment, it's extremely useful in our daily lives. Techs often use it to take temperatures. Note that temperature control is critical in the HVAC industry.

Even a 1°F difference in equipment state and compliance with standards, such as the proper temperature at which a supermarket must store meat, can make a significant difference. Precision is crucial.

Precise temperature measurements are critical for jobs like measuring air differences, superheat, and subcooling. HVAC techs typically use thermometers to measure the temperatures of air, water, refrigerant, and copper lines. These readings are critical in determining the cause of a potential hazard or defect.


Precise temperature measurements

When you heat organic and inorganic objects, they emit infrared energy, which is a portion of the electromagnetic light spectrum. The emissivity of a substance is the rate that which this energy is emitted and absorbed. It ranges from 0.0 to 1.0. Most infrared thermometers have an emissivity of .95 or.97, which includes the levels of materials generated from animals or plants. (Emissivity is substantially lower in materials with shiny surfaces, like polished metal.)

A lens in an infrared thermometer (also known as a pyrometer) gathers infrared energy from an object. Then, it channels it into a thermopile detector. It converts into electricity by the thermopile, displayed on the thermometer's LCD screen. Despite its complexity, this procedure takes only a few microseconds to complete.

A non-contact IR thermometer, unlike a probe thermometer, can only measure external temperatures. It's ideal for use from afar to check the temperature of a pizza oven or locate a hot spot on a grill. Restaurants, HVAC installations, home inspections, and car repair employ infrared thermometers.



Testo 830 Infrared Thermometer

During the hot summer months, most areas require air conditioning. The interiors of houses and offices can quickly heat up when the air conditioning stops operating. The incoming air temperature, intake, and air exiting the vents are compared using special thermometers. If such thermometers detect a rise in air temperature rather than a drop, you should service the air conditioner before it fully fails.

  1. Find the air intake, which is normally in the ceiling, the baseboard of a wall, or the floor on rare occasions. The air filter is positioned where the air intake is located.
  2. While the machine is running, place an infrared thermometer immediately on the air intake. To measure the temperature, turn on the thermometer and pull the trigger. It will display the temperature of the air entering the air conditioner.
  3. Take a step stool or ladder to one of the air vents and place it underneath it. Climb up until you're directly beneath the vent.
  4. To ascertain the air temperature coming out of the vent, place the thermometer immediately beneath the vent. Then, press the trigger.
  5. Take the air temperature going out of the vent and subtract it from the air temperature at the intake point. The temperature disparity is 20 degrees if the intake temperature is 85 degrees as well as the vent temperature is 65 degrees. The aircon works well if the temperature difference is greater than 15 degrees. If the difference is below 15 degrees, have a professional check the system because it's not cooling effectively.


Ice Bath

  1. Fill a big glass with ice to the brim.
  2. Pour in very cold water until it reaches a half-inch (1 centimetre) below the ice's surface.
  3. The ice bath is warmer than 32.0°F (0.0°C) if the ice floats up from the very bottom of the glass at all. Using a strainer, remove any surplus water.
  4. Give the ice mixture a gentle swirl and set aside for two minutes.
  5. Make a well of open water where no ice is floating, or tamp the ice down to create an available water layer at the top of the glass.
  6. Check that your infrared thermometer is at 0.95 or 0.97 emissivities setting.
  7. Place the lens or opening of your infrared thermometer directly above and perpendicular to the ice bath's surface.
    Note: If you hold your IF thermometer too far away from the ice bath's surface or at an angle, the sides of the container or even the table it's resting on will be included in your measurement, giving you an erroneous result.
  8. Press the button on your infrared thermometer. Make sure to take great care to ensure that the "field of view" is far inside the walls of the glass or container.


Digital thermometer readings are frequently converted between multiple temperature units, such as Celsius and Fahrenheit. Fahrenheit readings may be more relevant than Celsius ones, especially if you live in the United States. Even if your thermometer does not provide Fahrenheit readings, making the conversion manually takes only a few minutes.

We have two thermometers: a digital thermometer with only one power button and a more effective infrared thermometer.

  1. Ensure that the thermometer is turned off.
  2. Push and hold the power button for around 5-7 seconds, and the display panel will cycle between the following settings: "°C/SET, °F/SET."
  3. When the desired temperature unit shows on the display screen, release the power button. After you alter it once, the next boot will keep your current setting. If you adjust it to degrees Celsius once, it will stay that way until you re-adjust it.

Convert Celsius to Fahrenheit

If your infrared thermometer can't convert between Fahrenheit and Celsius, do it yourself.

  • To convert a Celsius reading to Fahrenheit, multiply it by 1.8 and add 32.
  • If your thermometer reads 48 degrees Celsius, your Fahrenheit reading would be (45 x 1.8 = 86.4 Plus 32) or 118.4 degrees Fahrenheit.




The precision of a thermometer is the most important feature. The accuracy of infrared thermometers is determined by the distance-to-spot ratio (D/S ratio). The maximum distance from which a thermometer may evaluate a certain surface area is shown by this ratio. For instance, if you need to measure the temperature of a 4-inch region with an IR thermometer with an 8:1 D/S ratio, the maximum distance from which you can correctly record the temperature is 32 inches (8:1 x 4). Larger ratios allow you to gauge temperature from a greater distance. However, when the distance between the two points grows, the surface area also grows.


The emissivity of a thermometer indicates how much infrared energy it may emit at any given time. IR thermometers with an emissivity value near 1.00 can read more materials than those with a lower value. Choose a thermometer with an adjustable emissivity level so you may modify the quantity of infrared energy emitted and correct for the energy reflected by the substance you're measuring temperature with.

Temperature Range

The temperature range of an infrared thermometer influences the job you can do with it. You might wish to invest in an IR thermometer with a wide temperature range to record a variety of processes at varying temperatures. Where higher resolutions are required to assure adequate temperature management of a given cycle, an infrared thermometer with a narrow temperature range is preferable.

Reading Speed

After starting the thermometer's reading procedure, the reading speed is the time it takes for the thermometer to produce an accurate reading. This factor is critical when measuring the temperature of a moving object or in situations where things heat up quickly.


Industrial infrared thermometers must be durable enough to last. The polymer nature of no-lens and Fresnel lens thermometers makes them robust and safe. Tough Mica lens thermometers, on the other hand, require a more durable shell and a carrying cover to keep the lens from cracking.


Even in low-light situations, a backlit screen makes it easy to read the temperature.


Because thermometers are fragile and may potentially be malfunctioning, a warranty is a must-have feature. Mica lens thermometers are more expensive than no-lens and Fresnel thermometers, which can be rather costly. If you're going to buy a costly thermometer, make sure it has a manufacturer's warranty.

Infrared thermometers are necessary when reading the temperature of a surface that is too unsafe to touch or practically impossible to access. These thermometers provide quick results and are easy to use, despite their complicated inner workings. However, before purchasing an infrared thermometer, determine the temperature range and application. You achieve accurate results. Make sure to operate the gadget correctly and in the proper location.



It's critical to get an infrared thermometer that can measure goods inside the temperature range that will be appropriate for your needs. Every infrared equipment on the market today is for a specific temperature range. It won't work if you try to measure something outside of that range. As a result, when choosing an infrared thermometer, consider what you'll be monitoring and the expected temperature ranges for those objects.

If you intend to buy an infrared thermometer for your aircon and other HVAC-related uses, then you should shop here at HVAC Shop! We have different infrared thermometers and other types of thermometers waiting for you.