Instruction Manual

748297-E June 2003

Model NGA2000 HFID

LON/Power Module

1.Disconnect wiring connectors, note locations.

2.Refer to Figure 4-20 on page 4-22. From the outside of the front panel, remove the two mounting screws.

3.Install replacement module in reverse order.

LED Indicator Assembly

1.Disconnect wiring connector, note lo- cation.

2.Refer to Figure 4-20 on page 4-22. From the inside of the front panel, remove the two hex nuts securing LED indicator assembly to front panel. Remove indicator assembly and o- rings (four).

3.Inspect o-rings for damage, replace if necessary. Install o-rings on re- placement indicator assembly, mount assembly on mounting studs with hex nuts.

4.Re-connect wiring connector.

Manual Ignite Toggle Switch

1.Disconnect wiring connector, note lo- cation.

2.Refer to Figure 4-20 on page 4-22. From the outside of the front panel, remove the toggle switch seal.

3.Pull the switch and o-ring out from in- side the front panel.

4.Inspect o-ring for damage, replace if necessary. Install o-ring on replace- ment switch, insert through front panel from the inside.

5.Install switch seal.

6.Re-connect wiring connector.

Burner Air Sensor

1.Disconnect wiring connector, note lo- cation.

2.Using an open-end wrench to hold the sensor fitting while using another open-end wrench to remove the sen- sor.

3.Replace the Teflon pipe thread tape on the treads of the sensor fitting.

4.Install sensor onto sensor fitting.

5.Re-connect wiring connector.

Fuel Sensor

1.Disconnect wiring connector, note lo- cation.

2.Using an open-end wrench to hold the sensor fitting while using another open-end wrench to remove the sen- sor.

3.Replace the Teflon pipe thread tape on the treads of the sensor fitting.

4.Install sensor onto sensor fitting.

5.Re-connect wiring connector.

4-24 Maintenance and Troubleshooting

Rosemount Analytical Inc. A Division of Emerson Process Management