Honeywell MeshGuard FTD-2000 User Manual page 16

MeshGuard User's Guide
Press [MODE], and it displays TWA. The TWA (time-weighted average) is the accumulated reading of the gas
concentration, divided by 8 hours, since the monitor was turned on.
Press [MODE], and the display indicates the Peak reading by alternating between "P" (for "Peak") and a numerical
value:
Press [MODE] to return to the current reading:
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