Instruction Manual

748297-E June 2003

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.

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.

CAUTION

PREAMP CONNECTORS

The electrical preamp connectors are fragile, handle with care to avoid breaking solder connection.

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.

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.

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.

4-4 Maintenance and Troubleshooting

Rosemount Analytical Inc. A Division of Emerson Process Management