We will check all the gas lines inside the grill by hooking up a gas pressure gauge and checking all visible fittings and do a timer check on holding gas pressure. From there we were able to determine that the hard piped fittings where holding pressure so we then opened up the gas flex lines shut off valves for the fixtures and found one hose leaking and a regulator that was burping improperly. We replaced the regulator and fixed the leaking flex hose. We found that the building sewer was backing up due to a clog before the grease trap we were able to run a snake down the clean-out outside and clear the clog.