
Turn on ‘ ’ icon while the indoor temperature is displayed. Turn on ‘ ’ icon while the
external probe temperature is displayed.
G. Maximum /minimum temperature record
Indicates the maximum/minimum temperature is displayed.
H. Maximum /minimum humidity record
Indicates the maximum/minimum humidity is displayed.
DESCRIPTION OF BUTTONS
THW301 has 3 major side buttons
1. [IN-OUT]
Press once to toggle the display of the indoor temperature to the probe temperature. Press
again to enable the auto-scroll function that will display the indoor temperature and the probe
temperature alternately for 5 seconds.
2. [MEM]
Press shortly to toggle for maximum, minimum or current temperature and humidity reading.
Press and hold 2 seconds to clear the maximum and minimum records.
3. [HEAT]
Press to toggle the display for indoor humidity and indoor heat index.
C/F slide switch and[RESET] button inside the battery compartment
4. [C/F]
Slide switch to C or F position to select temperature reading in Celsius or Fahrenheit
5. [RESET]
To activate system reset to the main unit during abnormal condition which will reset all settings
back to factory values
BATTERY INSTALLATION
1. Remove the battery door;
2. Insert 1 pieces AAA size 1.5V alkaline battery as indicate by the polarity;
3. Close the battery door.
Note: Replace the battery when the low battery indicator appears on the top corner of the
LCD.
HEAT INDEX FUNCTION
The heat index is an index that combines air temperature and relative humidity to determine an
apparent temperature — how hot it actually feels. The human body normally cools itself by
perspiration, or sweating, in which the water in the sweat evaporates and carries heat away from
the body. However, when the relative humidity is high, the evaporation rate of water is reduced.
This means heat is removed from the body at a lower rate, causing it to retain more heat than it
would in dry air. Press [HEAT] button to switch the display from humidity reading to the heat index.
The ‘Hot’ alert icon will be turned on if the heat Index is 32C or higher. That means there are
possible to cause sunstroke, heat cramps, and heat exhaustion if a man continues to expose
himself in such environment for a long period.