Introduction; Description - Extech Instruments RH25 User Manual

Introduction
Thank you for selecting the Extech Instruments Model RH25 Heat Index Psychrometer. The RH25
measures Temperature and Relative Humidity (using precision capacitance RH sensor). The RH25
also calculates and displays Heat Index, Dew Point, Wet Bulb, and Wet Bulb Globe temperatures.
The High Temperature Alarm feature alerts the user when Heat Index or Wet Bulb Globe levels
exceed user‐preset limits.
Data Hold and MIN/MAX/AVG memory utilities make it easier to recall important data.
This device is shipped fully tested and calibrated and, with proper use, will provide years of
reliable service. Please visit our website (www.extech.com) to check for the latest version of this
User Guide, Product Updates, and Customer Support.
Description
Meter
1. Sensor area
2. Display area (LCD)
3. POWER button
4. HOLD button
5. MODE button
6. Battery compartment on rear of instrument
Display
TEMP Temperature
AIR T Air Temperature
RH Relative Humidity
HI Heat Index
DP Dew Point temperature
WB Wet Bulb temperature
WB/HI Wet Bulb Globe temperature
MAX Maximum reading memory
MIN Minimum reading memory
AVG Average reading memory
HOLD Data Hold (freezes display)
BAT Low Battery symbol
% Percent units for RH readings
o Degrees symbol for temperature units
E Used to display temperature units C or F
2 RH25‐EU‐EN v1.0 5/13