Less ozone diffrence in SCD355

[amrnasser]

My GC SCD355 showing less ozone diffrence between ON and OFF postion (0.1 off and 0.2ON) I try to run 5 PPM H2S it showing only 0.5 ppm . Pressurw in detecor unit is 2.5 torr .

[muGC]

Sounds like you probably need to replace the ozone generator.

Take the left side panel off thedetector box and then the smaller panel hiding the ozone generator. If the ozone generator is very discolored (dark brown/black or yellow), this is another indicator it needs to be replaced.