Fieldpiece JL3RH Review: Wireless Psychrometer Probes
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Top pickFieldpiece JL3RHCheck price
The Fieldpiece JL3RH is a wireless psychrometer probe that measures air temperature, relative humidity, wet bulb and dew point and sends them to your phone. It belongs to Fieldpiece’s Job Link System, which also includes pressure probes, pipe clamps and manometers.
Check Fieldpiece JL3RH priceCheck Fieldpiece JL3KH6 price
Specs at a glance
Best for: Techs using Fieldpiece Job Link or SM-series manifolds who want wireless supply and return air, wet bulb and dew point.
- RH 0 to 100%; +/-2.5% RH from 10 to 90%, +/-5% outside that
- Temperature -40 to 250 F; +/-1 F from 32 to 113 F
- Reads wet bulb and dew point
- Wireless 2.4 GHz, 1000 ft line of sight; Job Link app and SM380V/SM480V manifolds
- 2 x AAA, about 150 h; auto off 2 h (can disable)
Why it stands out
- Flexible probe with sliding magnet for placing in ducts
- Feeds superheat target and airflow calcs in the app
- Long wireless range
Keep in mind
- Sold one at a time; you need two for supply and return
- 60 s typical RH response time
- Only a 1-year warranty
Best for: Techs replacing analog gauges with a hoseless wireless charging and airflow setup.
- Includes 2 JL3PR pressure probes, 2 JL3PC pipe clamps, 2 JL3RH psychrometers, padded case
- Pressure 0 to 580 psig, +/-1 psig best accuracy, 800 psig overload; 1/4 in flare
- Pipe clamp 1/4 to 1-3/8 in lines; -50 to 257 F, +/-1 F
- Psychrometer 0 to 100% RH +/-2.5%; -40 to 250 F
- 1000 ft wireless range; each probe 2 x AAA, about 150 h
Why it stands out
- Superheat and subcool in the app with pressure + pipe clamp
- Probes attach directly to service ports, no manifold hoses
- Pressures auto-calibrate for elevation
Keep in mind
- Six probes means twelve AAA batteries to manage
- Depends on a phone/tablet for readings
What the JL3RH does well
- Wet bulb and dew point. Relative humidity from 0 to 100%, plus calculated wet bulb and dew point, which feed airflow and superheat target calculations in the app.
- Range. Fieldpiece lists 1,000 ft of line-of-sight range.
- Flexible probe with a sliding magnet, so you can place it in a duct or on a return grille.
- Accuracy. Fieldpiece lists plus or minus 2.5% RH from 10 to 90% and plus or minus 1 F from 32 to 113 F.
- Battery life. Two AAA cells for about 150 hours.
Where it falls short
- One probe per box. You need two for supply and return.
- Slow RH response. Fieldpiece lists a typical 60 second response time.
- Phone required. Readings show in the Job Link app or on an SM-series manifold.
- Warranty. One year, limited.
Pair it with the rest of the Job Link system
The JL3RH is one piece of a larger set. The JL3KH6 charge and air kit adds two pressure probes and two pipe clamps for a hoseless superheat and subcool setup. The JL3KM2 manometer kit reads supply and return static pressure and calculates total external static pressure. Fieldpiece lists the JL3RH as compatible with the SM480V manifold, which we cover in our SM480V review.
Who should buy it
Techs who already own Fieldpiece Job Link gear or an SM-series manifold and want to check airflow and delta-T from one place. If you just need an air temperature, a pocket thermometer costs a fraction as much.
Frequently asked questions
Does the JL3RH come in a pair?
No. Fieldpiece sells it individually, so buy two if you want supply and return together.
What is the wireless range?
Fieldpiece lists 1,000 ft of line-of-sight range. Walls and equipment reduce real range.
What batteries does it use?
Two AAA batteries, rated for about 150 hours by Fieldpiece.
Does the JL3RH work with the SM480V manifold?
Yes. Fieldpiece lists the SM380V and SM480V manifolds among the devices that receive its readings.
Keep reading
Sources
Specifications and product details were checked against these sources:
