Completed one ccm maintenance on gas furnace located in basement, i inspected gas and exhaust to make sure they were up to code checked drain, I did not change filter as customer did it a couple days before one was left with him I cleared pressure tube, I cleaned flame sensor, I fired unit up watched run flames were very loud I turned gas pressure down although no codes were shown, I watched unit cycle again got inducer motor and blower amps, system performing as it should at this time.