An infrared thermometer can be an invaluable tool when diagnosing various engine related problems in your car. Whether it is measuring the temperature of various cooling components to isolate the source of an overheating issue, gaining clues as to the efficiency of your catalytic converter, trouble shooting your AC system, or identifying misfiring or non-firing cylinders, there is a place in every mechanic’s toolbox for an infrared thermometer when it comes to automotive diagnostics. Another group of people that uses infrared thermometers are those who track their cars. An infrared thermometer can give you a pretty good idea regarding whether items like brakes and tires are achieving optimal temperature and allow you to swap as necessary.
Considering the high level of utility and how many car mechanics are looking for these devices, we thought it wise to jot down a few considerations and tips to help you find the best infrared thermometer for the money.
What is an Infrared Thermometer?
An infrared thermometer, also often referred to as non-contact thermometers, temperature guns, laser thermometers, spot infrared thermometers, of infrared pyrometers are devices that can determine the temperature of objects without actually making contact with them.
An infrared thermometer works by measuring the thermal radiation emitted by an object and calculates temperature based on this value. The device contains a lens that focuses the infrared thermal radiation onto a detector which then converts this energy to an electrical signal that can be measured and converted into temperature. This is the long and technical way of saying that when you aim the laser light of the thermometer at an object, it tells you the temperature of that object.
What to Look For When Choosing a Non-Contact Thermometer?
There are only a few main things to watch out for when searching for an infrared thermometer. First and foremost, your biggest concern should be accuracy. Based on the way an infrared thermometer works, it’s easy for this type of device to pick up signal from items that are close to the component you are trying to measure. As such, you want to make sure your thermometer is equipped to deal with this to avoid erroneous readings. You will want at least an advertised accuracy of +/- 2% for automotive use. Make sure you get a temperature range of at least zero to 500 degrees Fahrenheit to cover automotive work.
You will also want to find a thermometer with a high D:S (Distance to Spot) ratio which means that the measurement area is small compared to the distance you measure from. This means you don’t have to hold the device right next to the component you are measuring to get an accurate reading. Remember, when you are taking temperatures in your engine bay, everything is either hot or moving (such as engine belts) and you don’t want to have to get your hand close to this stuff if you don’t have to.
The other things worth paying attention to are general build quality and price as there are some high priced pieces of junk out there and similarly some outstanding units that can be had for a very reasonable price. To save you some time, we will be showing you a few of the latter.
The Best Infrared Thermometers
Now that we’ve covered the basics and given you the appropriate background info, here is a breakdown of our favorite infrared thermometers for automotive repair.
Fluke 62 MAX Infrared Thermometer
When it comes to calibrated measurement tools, Fluke is widely known as one of the best manufacturers around. Their equipment is found everywhere in industry from automotive to communications to electrical.
There are a number of things that make the Fluke 62 MAX really great. First, temperature ranges from -20 to 923 degrees Fahrenheit, which is going to be more than enough on either end for wrenching on your car. The minimum accuracy is the greater of +/- 1.5% or +/- 1.5 degrees Celsius and the distance to spot ratio is a generous 10:1 so you won’t have to make contact with your scalding hot thermostat when you take a temperature reading. The device is IP54 rated for dust resistance and water resistance, which is imperative in an automotive environment.
The display is digital and is very easy to read. It shows temperature readout, emissivity setting, maximum temperature, minimum temperature, temperature difference, and also an average temperature readout. These functions are helpful for various reasons when working on your car and you’ll find that you use them all occasionally. Another huge benefit to the Fluke 62 MAX is that it uses AA batteries which can be found pretty much anywhere.
As far as build quality, the Fluke is unrivaled. The thermometer is super rugged, and Fluke advertises that it is capable of surviving a drop from 3 meters (10 feet). As far as price, there are definitely cheaper infrared thermometers on the market, but you get what you pay for. We give the Fluke 62 MAX our highest recommendation as we think it is worth the money.
EnnoLogic e650D Dual Laser Infrared Thermometer
The EnnoLogic e650D is a dual laser infrared thermometer that we really like. It is sleek and simple, but has all the features that you’d expect from a good infrared thermometer. The measurement range is from -58 to 1202 degrees Fahrenheit, which is quite vast. Accuracy is the greater of +/- 1% or +/- 2 degrees Celsius, which is pretty darn good.
The thermometer comes equipped with a dual laser, which helps align the tool precisely with respect to the component you are trying to analyze. The distance to spot ratio is a10:1, which matches the that of the Fluke above. Emissivity is adjustable which allows for more accurate readings across a wider range of objects and materials.
A 9V battery powers the system, which isn’t quite as convenient as AA or AAA batteries, but they are still widely available. Other notable features include a scan feature that saves and displays maximum, minimum, and average temperature. There is also a log of 20 saved temperatures that you can refer to as well as high and low temperature alarms that you can set that will sound if the temperature measured dips out of that range.
All of the above features combined with an attractive price (about 75% of the price of the Fluke 62 MAX) and a 10 year warranty make this an incredible value buy. You won’t get quite the same durability as you would with the Fluke, but the EnnoLogic eT650D is a great infrared thermometer for occasional home garage use.
Raytek MT6 Non-contact MiniTemp Infrared Thermometer
Our third and final favorite of the infrared thermometers available on the market is the Raytek MT6 Non-contact MiniTemp Infrared Thermometer. It sports a temperature range of -20 degrees to 932 degrees Fahrenheit, which matches that of the Fluke. Accuracy is the greater of +/- 1.5% or +/- 1.5 degrees Celsius which is similar to both of the other units we reviewed. The MiniTemp is a single laser system. The distance to spot ratio is 10:1, which is similar to the other two and perfect for automotive use.
The backlit display is very large and easy to read. The display will provide both current as well as maximum readings when scanning. The tool is powered by a 9 volt battery, which is workable but not as ideal as more ubiquitous battery types.
Build quality is solid and similar in robustness to the EnnoLogic, with ergonomics to match. Raytek is proud of their ergonomic work on this thermometer, going so far as to call it award winning. While it feels nice in hand, we wouldn’t say that the ergonomics are such an improvement over the other two that they should heavily influence your buying decision.
Overall, Raytek builds a great infrared thermometer that is certainly worthy of consideration. It is similarly priced to the EnnoLogic and between the two it comes down to the features that most interest you (unless durability is your goal in which case stick with the Fluke).
So there you have it, a quick breakdown of what to look for when buying an infrared thermometer. While our guide is written specifically with the automotive repair crowd in mind, we would be remiss if we didn’t at least mention some of the other applications you will also be able to use your infrared thermometer for. Infrared thermometers are used in many other places including frying pan and oven temperature measurement in precision cooking, around the home for ducting and ventilation systems, any fixture or appliance with a cooling system such as a refrigerator or freezer, in medicine for taking body temperature, as well as for a number of other various hobbies and crafts. Our favorites are specific to the automotive industry and as such, requirements for the above alternative uses may be a little bit different.
That said, there are many different infrared thermometers on the market, and while we have picked our favorites, there are other great ones out there. If none of the three we have picked are quite right for your application, have a look at some other options available out there on the market. We hope you have found this guide useful and happy wrenching!