How long does it take to start up the FD08 and VOC08 properly? VOC08

Briefly press the PWR button. The LCD will illuminate and immediately begin scrolling “0s” across the five positions on the upper readout to indicate that it is warming up. During the warmup period, the meter will burn off any dust on the formaldehyde sensor inside the vented ball. If this is the first use of the meter or if it has not been powered on for a long time, the warmup period may last as long as several hours.

Normally, it takes 1 to 15 minutes for the scrolling to stop. Once it stops, the upper readout will begin counting down from 9999 through 8888 and 7777 all the way to 0000. When the upper readout reaches 0000, the upper readout will begin reading 0.00 ppm.