Emerson Rosemount Oxymitter DR, Reference Manual

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The cell flange has a notch that you can use to gently pry the flange away from the
probe. The contact pad inside the probe will sometimes fuse to the oxygen sensing
cell.
7. If the cell is fused to the contact pad, push the cell assembly back into the probe
(against spring pressure) and quickly twist the cell assembly.
The cell and contact pad should separate. If the contact pad stays fused to the cell,
you need to install a new contact/thermocouple assembly.
8. Disconnect the orange cell wire at the probe electronics end of the strut by cutting
the wire.
9. Withdraw the cell with the wire still attached.
10. Remove entire electronics per 1 and 2 in Replace entire electronics (with housing)
11. If the contact and thermocouple assembly is damaged, replace the assembly or the
contact pad.
Refer to
Replace contact and thermocouple assembly to replace the contact and
thermocouple assembly. The cell replacement kit includes instructions for replacing
the contact pad.
12. Remove and discard the corrugated seal.
13. Clean the mating faces of the probe tube and cell.
14. Remove burrs and raised surfaces with a block of wood and a crocus cloth.
15. Clean the threads on the probe flange and flame arrestor hub.
16. Apply a light coating of anti-seize compound to both sides of the new corrugated
seal.
17. Assemble the cell and flange assembly and corrugated seal to the probe tube. Make
sure the calibration tube lines up with the calibration gas passage in each
component. Apply a small amount of anti-seize compound to the screw threads and
use the screws to secure the assembly. Torque to 35 in.-lb. (4 N-m).
18. Apply anti-seize compound to the probe threads, flame arrestor hub, and
setscrews.
19. Reinstall the flame arrestor on the probe.
20. Using pin spanner wrenches, torque to 10 ft.-lb. (14 N-m).
21. Secure the flame arrestor with the locking setscrew. Torque to 25 in.-lb. (2.8 N-m).
22. If applicable, reinstall the vee deflector, orienting apex toward gas flow. Secure with
the setscrew and anti-seize compound. Torque to 25 in.-lb. (2.8 N-m).
23. On systems equipped with an abrasive shield, install the dust seal gaskets with
joints 180 °apart.
24. If previously removed, instll the entire electronics per 3 and 4 in Replace entire
electronics (with housing) .
25. Follow the instructions in Install probe . Install the transmitter into the stack or duct.
If there is an abrasive shield in the stack, make sure the dust seal gaskets are in place
as they enter the 15 ° reducing cone.
Maintenance and service Reference Manual
October 2019 00809-0100-4880
62 Emerson.com/Rosemount