User Manual

2RH25‐EU‐ENv1.05/13
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
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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
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