10. UEi Test Instruments DTH35
While the UEi Test Instruments DTH35 (around $92) looks small and unobtrusive, it can grow to twice its length by removing the probe cover and using it as an extension holder. Regardless of how far away from your face it gets, you should be able to read the clear display.
- Strong magnetic mount
- Plastic housing is thin
- Readings upside down for lefties
9. Fieldpiece PRH2
The Fieldpiece PRH2 (around $68) is incredibly easy to carry with you on service calls, as it’s the size and shape of a large pen, and can even clip on to your breast pocket, just like one. When it’s time to use it, all you have to do is unscrew the twist-on cap.
- Brightly backlit display
- Accurate wet bulb measurements
- Too fragile for extensive daily use
8. General Tools EP8706
The General Tools EP8706 (appx. $72) is easy to use, as both the display and the buttons are large and simple to decipher. It purports to have a 60-second response time, but you may need to wait a little longer than that to get a truly accurate reading.
- Works in temps up to 122 degrees f
- Comes calibrated out of the box
- Struggles in extreme cold
7. Mengshen M350
The Mengshen M350 (around $34) is suitable for more than just HVAC technicians, as it functions admirably in laboratories, greenhouses, apartments, and other locations. Every serious horticulturist should have one, as well as anyone who suffers skin or respiratory issues in their home.
- Ergonomic design
- Can disable automatic shutoff
- Takes a long time to obtain readings
6. Bacharach 0012-043
It’s somewhat old school, but the Bacharach 0012-043 (about $117) makes up for it by being incredibly accurate. It folds open, with a pair of thermometers on one side and a slide rule on the other, so be prepared to do a little bit of quick arithmetic.
- Compact and lightweight
- Good for use in science classes
- Expensive for what it is
5. Mengshen M86
The Mengshen M86 (about $26) has a ten-second response time, enabling you to get almost-immediate readings without having to wait for your device to figure things out. Those results are easy to see, as well, thanks to the adjustable LCD screen.
- Automatic shutoff preserves battery
- Good budget option
- Humidity readings jump around
4. General Tools EP8710
If you’re hard on equipment, the General Tools EP8710 (around $59) is an investment worth making. You can toss it in a tool bag and rattle it around without worry. Even better, it won’t take up much room in there, and the screen is easy to read even if it gets a little scratched up.
- Can be calibrated in the field
- 9v battery included
- Data hold button
3. Extech RHT510
Tech junkies will appreciate the Extech RHT510 (appx. $97), as it’s a fairly complex piece of equipment. It can measure extreme temperatures, as the included K-probe can chart up to 480°F, while the meter is capable of recognizing 2,372°F when paired with other devices.
- Built-in tripod mount
- Made of durable hard plastic
- Nickel-plated wiring
2. PDI DP-110
The PDI DP-110 (appx. $44) has a flexible neck that enables you to finagle the sensors into tight spots, like air ducts or plenums. The blue backlight is clearly visible in dark areas without blinding you, helping to preserve your eyesight for a few more years.
- Comes with carrying pouch
- Calculates ambient temperature
- Minimum-maximum function
1. Fieldpiece SDP2
The Fieldpiece SDP2 (about $263) can take four evaporator measurements simultaneously, giving you a complete real-time view of what’s going on inside your HVAC system. The dual probes are detachable and can transmit data to the handheld unit or to the companion mobile app.
- Reacts to changing conditions
- 38-inch telescoping probes
- Magnetic hanger