Yellow Jacket
Yellow Jacket 69008 HygroThermoPsychrometer
Measures humidity 0–100 % and temperature –4 °F to 122 °F with ±3 % RH and ±1 °F accuracy
- ColorTransparent
- Measures humidity 0 to 100 % with ±3 % accuracy
- Reads temperature -4 °F to 122 °F within ±1 °F
- Calculates wet bulb down to -69 °F and dew point to -90.4 °F
- Thermistor sensor delivers 0.1 % humidity resolution on LCD
- Surface temperature range spans 4 °F to 140 °F
HVAC Diagnostics Tool
The Yellow Jacket 69008 HygroThermoPsychrometer measures temperature, relative humidity, wet bulb and dew point for HVAC technicians and facility managers who need a single handheld instrument for system diagnostics and indoor-air-quality checks. Its thermistor sensor and LCD display deliver simultaneous readings across psychrometric parameters.
Replaces Separate Meters
This unit combines the functions of a thermometer, hygrometer and psychrometer so technicians no longer carry three individual devices to capture dry-bulb, wet-bulb and dew-point data. The jump is worth it when service calls require rapid switching between temperature, humidity and calculated psychrometric values on one screen.
Sustained Field Use
The thermistor sensor maintains ±1 °F temperature accuracy and ±3 % relative humidity accuracy across the full operating span from -4 °F to 122 °F, while dew-point calculations remain stable from -90.4 °F to 122 °F during extended measurement sessions. The 0.1 % humidity resolution supports consistent trend logging without drift during long-running environmental assessments.
Highlights
- Measures humidity 0 to 100 % with ±3 % accuracy
- Reads temperature -4 °F to 122 °F within ±1 °F
- Calculates wet bulb down to -69 °F and dew point to -90.4 °F
- Thermistor sensor delivers 0.1 % humidity resolution on LCD
- Surface temperature range spans 4 °F to 140 °F
Specifications
| Brand | YELLOW JACKET |
|---|---|
| Color | Transparent |
Questions about this item
What clearance does the Yellow Jacket 69008 need for its LCD display and thermistor sensor to read ambient air correctly?
The unit is a handheld psychrometer with an integrated LCD and exposed thermistor; allow a few centimetres of free air around the sensor so the 0.1 % humidity resolution and ±1 °F temperature accuracy are not affected by body heat or direct sunlight.
How do I start the Yellow Jacket 69008 for the first time, and what common step causes wrong dew-point readings?
Insert the required batteries, power on, and let the thermistor stabilise for several minutes before logging; skipping the warm-up period is the step that most often skews the -90.4 °F to 122 °F dew-point range.
When should I replace the sensor or recalibrate the Yellow Jacket 69008 to keep humidity accuracy within ±3 %?
The thermistor sensor is not user-replaceable; if readings drift beyond the stated ±3 % RH tolerance, return the instrument to a qualified calibration lab rather than attempting field adjustment.
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