Emerson Process Management 760004-A - Manual (Page 67)

Instruction Manual
760004-A
February 2002
Rosemount Analytical Inc. A Division of Emerson Process Management Troubleshooting 5-1
Model NGA 2000 HFID
SECTION 5
TROUBLESHOOTING
5-1 TROUBLESHOOTING CHECKLIST
a. Safety System
1. Verify purge supply pressure at bulk-
head is between 10 and 20 psig.
2. Check case for leaks.
3. Check burner for leaks.
4. Verify purge pressure sensor tube
connection.
5. Verify purge out port is vented to at-
mospheric pressure.
6. Verify Safety PCB connector J2 is
attached.
7. Check for a +24V power glitch.
8. Verify that there is no large vibration
shock.
9. Check for external leak in purge line.
10. Verify case pressure is greater than
0.5” of water.
11. Check case for over-pressurization.
12. Verify the purge flow/pressure switch
harness is routed away from the sole-
noid valves.
13. Verify the purge timer is counting.
14. Verify purge timer jumper is correctly
installed.
15. Verify Internal purge pressure is
greater than 5.5 psig.
16. Verify the purge gas switch has been
activated.
b. Ignition
1. Verify that the fuel pressure/flow is
correct.
2. Verify that the burner air pres-
sure/flow is correct.
3. Verify that the igniter is generating
enough heat.
4. Verify the burner exhaust is vented to
atmosphere.
5. Verify safety system has been acti-
vated.
6. Verify the manual switch is operating
correctly.
7. Verify auto-ignite parameters are
properly set.
8. Verify burner is properly sealed.
9. Verify quality of air supply is good.
10. Verify quality of fuel supply is good.
11. Check burner tip for damage.
12. Check air and fuel restrictor for cor-
rect flow.
13. Check burner tip alignment.
14. Verify burner cone is tight.
15. Check burner air and fuel lines for
leaks.
16. Verify oven temperature is greater
than 85 °C.
17. Verify the reference thermistor is
100K ohm ±15% at 25 °C.