Sentry ST312A Instruction Manual page 12

 Manual reset mode: The Reset Indicator on screen
Press the Rest button once to reset to background manually and the Reset
Indicator on screen flashes 1 sec. (Only in Manual reset mode.)
 Auto reset Mode: TheReset Indicatoron screen
Under auto reset mode, pressing Rest Button is invalid, since the
detector will rest automatically.
●
MUTE Button
Press the Mute button to toggle the audio alarm on and off.
The buzzer alarm is turned off: The MUTE icon
The buzzer alarm is turned on: The MUTE icon
※ The detector will automatically default to previous MUTE ON/OFF setting
after re-start
The buzzer alarm is OFF

Under the MUTE mode, all audible beeps are off.
The buzzer alarm is ON

 Button Tone
The buzzer gives one beep when any of button is pressed.
 Detection Tone
The buzzer beeps every 2 seconds when no leak activity is found.
The buzzer becomes rapid when leak signal is approaching.
The fast beeps is given, the high density refrigerant is detected.
●
Tip Light LED Button
will show for 2 secs.
will show for 2 secs.
disappears and
appears and
will be appeared.
will be off.