Harbor Freight Laser Thermometer

The phone rang over the weekend….a Jeep friend from Colorado was calling to discuss tranny coolers, among other things.  As we discussed coolers and such, he asked me if I had tried the HF laser thermometer.  It was currently on sale for just $39.99.  He had recently bought one and took it to work where he had the local calibration lab verify its accuracy….it checked out just fine….within 2 degree Fahrenheit, which is within the published specs of the thermometer.  While out and about today, I stopped by the local HF store and picked one up.  I’ve wanted one for quite some time and the price on this one was good enough for me.


This non-contact thermometer is quite similar to many of those on the market.  (and it is probably sold under several different labels)  The typical pistol grip design makes it easy for one-hand operation.  The 9 volt battery is stored in the handle and the red trigger turns the unit on.  Releasing the trigger will turn the unit off after approximately 7 seconds. 

A diagram on the head of the thermometer shows the distance to spot ratio, which is 8:1.  In other words, if you wish to measure a 1″ diameter area, you should hold the thermometer approximately 8″ back from the object.  If the area to measure is approximately 8″ in diameter, you should position the thermometer approximately 65″ away from the object.  In other words, the measured area on the target increases as the distance to the target increases. 


The controls are very straight forward.  A Fahrenheit and Celsius button switches between the two temperature scales.  The yellow button backlights the LCD display for improved viewing in low light situations.  The laser is enabled by pressing the red button after pulling the trigger.  The laser will stay active (using the trigger) until the unit cycles off.

As long as the trigger is depressed, the temperature will change if the target area temp changes or you move the laser across the target to an area where the temperature is different.  Releasing the trigger puts the thermometer in the HOLD mode.  The displayed temp will remain for 7 seconds (the unit turns off) or it can be updated by again pressing the trigger. 

The measurement range of the thermometer is -20 to 270 degrees Celsius or -4 to 518 degrees Fahrenheit with an accuracy of +/- 2%.  The thermometer will obtain an accurate target temperature reading in under 1 second.  The thermometer comes with a 1 year warranty. 

Non-contact thermometers are certainly not new on the mechanic’s scene.  I opted to do this review so you could see the features and price of this Harbor Freight offering.  I realize that HF products often get a bad rap….and sometimes rightly so.  Assuming this one continues to work as intended, I feel it is a pretty good buy and can be invaluable when doing A/C work, cooling system diagnosis, checking differential temps, and other vehicle components. 

Good trails and remember to TREADLightly!