Emerson Process Management ROSEMOUNT NGA2000 HFID - Manual (Page 63)

Instruction Manual
748297-E
June 2003
Rosemount Analytical Inc. A Division of Emerson Process Management Maintenance and Troubleshooting 4-25
Model NGA2000 HFID
Burner Air and Fuel Regulators
1. Disconnect the two tubes and the
sensor fitting on the rear of the regu-
lator, note locations.
2. Replace the Teflon pipe thread tape
on the threads of the sensor fitting.
3. Remove the regulator and o-ring.
4. The replacement regulator comes
with two panel mounting nuts, remove
both and discard one of them.
5. Inspect o-ring for damage, replace if
necessary. Install o-ring onto regula-
tor threaded shaft.
6. Insert regulator into front panel, se-
cure with mounting nut.
7. Re-attach the three tubes.
Purge Air Regulator
1. Remove the regulator mounting nut,
remove mounting bracket.
2. Loosen nut on tee fitting attached to
purge air flow switch.
3. Disconnect tube at elbow, remove
regulator.
4. Remove the two plugs, elbow and
male adapter fittings from the regula-
tor.
5. Replace the Teflon pipe thread tape
on the two plugs, the elbow and the
male adapter and install into replace-
ment regulator.
6. Connect tube to elbow, insert male
adapter into tee fitting.
7. Install mounting bracket onto regula-
tor, hand snug mounting nut.
8. Attach mounting bracket to front
panel, tighten regulator mounting nut.
Purge Air Flow Switch and Diffuser
1. Unscrew flow switch from tee fitting.
2. Replace Teflon pipe thread tape on
tee fitting.
3. Remove diffuser from flow switch and
install into replacement flow switch.
4. Install replacement flow switch.
5. Install purge switch onto tee fitting.
6. Re-connect tubes.
Burner Air Solenoid Valve
1. Disconnect the tube at the top elbow
fitting.
2. Disconnect the tube at the tee fitting,
remove valve analyzer module.
3. Holding the air ignite restrictor, un-
screw the solenoid valve.
4. On the solenoid valve, remove the
connector fitting.
5. Replace the Teflon pipe thread tape
on the elbow, connector and restric-
tor.
6. Verify replacement solenoid valve
wires (flat side of body) are exiting on
the same side as the COM port as
shown in Figure 4-20 on page 4-22. If
not, use an open-end wrench to hold
the N.O. hex port while rotating body.
7. Install air ignite restrictor into N.C.
port.
8. Install elbow into COM port and con-
nector fitting into N.O. port.
9. Re-connect tubes.