Emerson Process Management ROSEMOUNT NGA2000 HFID - Manual (Page 42)

Instruction Manual
748297-E
June 2003
4-4 Maintenance and Troubleshooting Rosemount Analytical Inc. A Division of Emerson Process Management
Model NGA2000 HFID
Oven Disassembly
1. Refer to Figure 4-4A on page 4-5.
Remove the four retaining screws on
the oven cover, remove cover.
2. Remove the two screws and one nut
securing the outer oven front panel to
the outer oven, remove front panel.
3. Remove the nuts and ferrules from
sample in and sample bypass out.
CAUTION
PREAMP CONNECTORS
The electrical preamp connectors are
fragile, handle with care to avoid
breaking solder connection.
4. Refer to Figure 4-4B on page 4-5.
Remove the two nuts and washers
from the electrical preamp connectors
on the inner oven front panel. Do
not unsolder these connections.
5. Unscrew the three screws from inner
front panel and remove it.
6. Refer to Figure 4-4C on page 4-5.
Remove the two hex nuts securing
the burner to the bottom of the inner
oven.
7. Disconnect the sample input and
output bypass fittings.
8. Lift the burner/thermal block up and
out, while disconnecting exhaust.
Reverse procedure for installation.
b. Burner Sensor, Detectors and Ignitor
This section covers burner components
which can be replaced without removal of
oven from the chassis.
Temperature Sensor
1. Refer to Figure 4-4A on page 4-5.
Remove the four screws on the oven
cover, remove cover.
2. Refer to Figure 4-5 below. Remove
the burner cap retainer.
3. Disconnect the temperature sensor
wiring connector, note location.
4. Remove the temperature sensor.
5. Insert replacement sensor.
Note
The leads of the temperature sensor
must be leading away and down from
the sensor to enable proper fit of
burner cap retainer.
6. Install the burner cap retainer. U-slot
must be located above temperature
sensor.
7. Re-attach wiring connector.
8. Install oven cover.
RTD Detector
1. Refer to Figure 4-4A on page 4-5.
Remove the four screws on the oven
cover, remove cover.
2. Refer to Figure 4-5 below. Loosen
the set screw securing RTD detector.
3. Disconnect RTD detector wiring
connector, note location.
4. Gently grasp RTD detector wires and
pull out of hole.
5. Insert replacement RTD detector into
hole, snug down set screw.
6. Re-attach wiring connector.
7. Install oven cover.