Teledyne API Model 200AU NOX Analyzer Instruction Manual, 02293, Rev. F
8-9
8.5 Replacing the Molybdenum Converter The Molybdenum Converter is located in the center of the instrument, refer to Figure 2-5 for its
location. Refer to Figure 8-4. The heater, thermocouple, converter is designed to be replaced as a
single unit.
1. Turn off the power to the M200AU and allow the converter to cool.
2. Remove the entire assembly from the chassis
A. Remove the pneumatic fittings from the valves.
B. Remove the power to the valves, thermocouple wire and cartridge heater.
C. Remove the converter assembly from the chassis by loosening the 4 captive screws that
secures the assembly to the chassis.
CAUTION
The converter operates at 315ºC. Severe burns can result
if not enough time is allowed for the assembly to cool. Do
not handle assembly until it is at room temperature.
3. Disconnect the gas fittings and power cable grounding from the can.
4. Remove the valve assembly and bottom bracket and re-attach those two parts to the
replacement moly assembly.
5. Re-attach the pneumatic fittings and valve assembly to the can.
6. Install the assembly back into the analyzer. Re-attach the electrical and pneumatic
fittings. Leak check the assembly when completed.
7. Turn the power back on. The insulation can emit a burnt odor for the first 24 hours, this is
normal. Allow the converter to burn-in for 24 hours, then re-calibrate the instrument.