YM CEMS. MCS 100 E stop pump, make good at cable Transduce Flowsic 100 bottom side, replace snap ring at flange MCS 100 E top side also replace filter top flange. Write reading CO around 965 PPM and SO2 around 165 PPM before replace snap ring. Recode reading CO around 615 PPM and SO2 around 65 PPM after replacing ( ADI & KISS ADRIANUS )