User Manual - Model AN25 - Hygro Thermo-Anemometer
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Meter Description
Battery Replacement
Vane impeller
Relative Humidity & Temperature sensors
LCD display
POWER button
Switching the Meter ON/OFF
HOLD button
• Press the POWER button to switch the meter ON
• Press and hold POWER for approx. 3 seconds to switch OFF
• The meter’s Auto Power OFF feature turns the meter OFF after 15
minutes of inactivity
Changing the Air Velocity Units
With the meter in air flow measurement mode press HOLD for approx. 3
seconds to change air flow units from m/s, KMH, M/H, FPM, BFT, KNT
and then back to m/s. See Specifications for icon definitions.
Change Modes and Temperature units
MODE button
Battery compartment (on rear)
Tripod mounting hole
Impeller set screw (on side)
The meter has a low battery indicator (BAT). Important: Turn the meter
off before opening the battery compartment. Using a coin, turn the
battery compartment cover COUNTER-CLOCKWISE to remove it. Once
opened, observe the position of the battery, placing the new one in the
same position. Secure the battery compartment cover and dispose of
the lithium battery in accordance with local, state, or national disposal
Never dispose of used batteries or rechargeable batteries
in household waste.
As consumers, users are legally required to take used
batteries to appropriate collection sites, the retail store
where the batteries were purchased, or wherever
batteries are sold.
Disposal: Do not dispose of this instrument in household waste. The
user is obligated to take end-of-life devices to a designated collection
point for the disposal of electrical and electronic equipment.
• Press MODE button to select the desired mode: WNCL (wind-chill),
TEMP, RH, HI (heat index), DP (dew point), WB (wet bulb), WBGT (wet
bulb globe), and back to m/s.
• From any temperature mode press the HOLD button to change
temperature units (°C / °F).
• With the meter ON press the POWER button. The MAX icon will
display on the LCD with the highest (maximum) reading.
• Press POWER again. The AVG (average) icon will display on the LCD.
Press the POWER button to step through the averaging time
selections (5sec, 10sec, and to 13sec). After selecting the averaging
time the meter will begin averaging readings.
• To exit the MAX/AVG mode, repeatedly press the POWER button until
MAX and AVG icons switch OFF.
Data Hold
• Press the HOLD button to freeze the displayed reading. The HOLD icon
will appear on the display.
• Press HOLD button again to return to normal operating mode.
Auto Power OFF
• The meter will power OFF after about 15 minutes of inactivity.
• To disable Auto Power OFF: With the meter switched OFF, press the
HOLD and POWER buttons until the meter switches ON.
• The 'n' icon will be displayed on the LCD and the meter will return to
normal operating mode.
• Now the meter will not switch OFF until the user manually switches it
OFF. Note that on the next cycle of power, the meter will revert to the
Auto Power OFF mode.
Error Messages
Er1: Sensor Error (replace unit); Er2: Measurement out of range
Important Note: If the meter is placed near a source of electricity the
electrical signal may affect the meter’s displayed reading.
Impeller Replacement
m/s (meters per second)
FPM (feet per minute)
0.40 to 25 m/s
80 to 999 ft/min
1000 to 4922 ft/min
KMH (kilometers per hour) 1.4 to 90.0 km/hr
M/H (miles per hour)
0.9 to 55.9 mph
BFT (beaufort)
0 to 10
KNT (knots)
0.8 to 48.6 knots
Temp./WNCL (Wind-chill) -15 to 50oC (5 to 122oF)
RH (relative humidity)
5 to 95% RH
WB (wet bulb)
-15 to 50oC (5 to 122oF)
DP (dew point)
-75 to 50oC (-103 to 122oF)
HI (heat index)
-35 to 205oC (-31 to 401oF)
WBGT (wet bulb globe)
-29 to 54oC (-20 to 130oF )
0.1 m/s
0.1 ft/min
1 ft/min
0.1 km/hr
0.1 mph
0.1 knots
0.1% RH
± (3%FS)
The replacement part number for the impeller kit is AN25-V (two
impellers are supplied). Loosen and remove the impeller set screw (9)
and then, from the back of the meter, turn the impeller counterclockwise to remove. Insert new impeller and turn it clockwise to lock
it. Insert and tighten the impeller set screw to complete the
± 1 BFT
± (3%FS)
± 1oC (± 1.8oF)
± 3% RH *
*@25oC 10-90%RH otherwise ±5%RH
Copyright © 2013-2017 FLIR Systems, Inc.
General Specifications
Max/Avg/Hold Modes
Operating conditions
Power supply
28 x 14mm (1.1 x 0.5”) LCD with low battery &
multifunction indicators
Max shows highest reading; AVG averages readings;
Data Hold freezes the display
0 to 50oC (32 to 122oF) / < 80% RH
Lithium battery (CR-2032 or equivalent)
152 x 40 x 18mm (6.0 x 1.6 x 0.7”); 60g (2.1 oz.)
All rights reserved including the right of reproduction in whole or in part in any form
ISO-9001 Certified
AN25-en-GB_V1.4 3/17
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