Ametek TM2000 Pro, User Manual

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7-6 | TM2000 Oxygen Analyzer
Furnace Replacement
Disconnect power from the sensor and control unit and allow the
sensor to cool before replacing parts inside the sensor.
Do the following to replace the furnace (Figure 7-2):
1. Disconnect the furnace lead wires from terminals R and S on the sensor
board and slide the furnace wires through the sensor board conduit hole.
2. Loosen the cable clamp nut on the sensor board that holds the thermocouple
wires (red and yellow). Disconnect the thermocouple wires from terminals
C and D on the sensor board and pull these wires through the sensor board
conduit hole.
3. Remove the two furnace bracket screws. Remove the front bracket screw
with a flat blade screwdriver and remove the back one by hand. Keep these
screws.
4. Lift the furnace off the furnace posts.
5. Remove the screw and accompanying lock washer from the thermocouple
mounting tab (save the screw and lock washer to install the thermocouple
into the new furnace). Pull the thermocouple straight up and remove it from
the furnace. Keep the thermocouple, screw, and lock washer for when you
replace the furnace.
6. Place the new furnace over the furnace mounting posts (thermocouple should
be on your right as you face the front of the sensor).
7. Tighten the furnace bracket screws. Hand tighten the bracket screw under -
neath the furnace, then tighten the other screw with a flat blade screwdriver.
Ensure that the furnace is completely seated into the furnace mounting posts.
8. Reverse the actions taken in Step 1 and 2 above. For the thermocouple wires,
the red wire connects to terminal D, the yellow wire connects to terminal C.
Polarity is not required for the furnace wires.