Extech HD550 Psychrometer InfraRed Thermometer

The Extech HD550 builds on the functionality of the HD500 by offering a three-in-one solution for measuring temperature, relative humidity and water vapour. Unlike other thermometers, this Extech model utilises patented infrared technology to ensure that accurate readings can be made without the equipment coming into contact with the object you’re measuring.

The added function on the Extech HD550 is the water vapour capability, and this measurement is presented in grams per pound. This can be extremely useful when combined with the humidity meter in maintaining a consistent environment for industrial spaces, greenhouses and offices. As standard, this Extech inspection equipment can gauge temperatures of up to 500 degrees Celsius with a margin of error of two degrees – however, when the Type K probe is used, this measurement range can be extended to 1,372 degrees C with an improved accuracy level of one degree. The lower range of the Extech HD550’s measurement range also decreases from -50 to -100 degrees C.

The humidity meter has the ability to measure RH of all levels – right from 0% to 100%, and will always be accurate to 2%. If this is not the case, the machine will notify you so the Extech HD550 can be calibrated with equipment that’s sold separately. When you are using the infrared technology, the distance-to-target ratio is 30:1, which means that the distance you are away from the object being measured should be 30 times larger than the diameter of the red mark provided by the laser pointer.

The LCD display is triple backlit, although it is recommended that you use this somewhat conservatively to prevent battery life being diminished too quickly. If you want to bring the equipment you use for home inspections into the 21^st century, and combine the accuracy of thermometers with a humidity meter and water vapour analyser, the Extech HD550 ticks all the boxes.