Gemini 501-B - Routine Maintenance; Problem Diagnostics; TABLE 1 Problem Diagnostics

16
6.3 Routine Maintenance
The only periodic maintenance for the instrument is to change the vacuum line filter element when the color
of the filter element turns red.
During a test, oil in the reservoir is oxidized continuously and would contaminate fresh oil added to it. The
process would eventually affect the test results. We recommend that after about 5-6 oil additions to the
nebulizer reservoir, the entire content should be discarded. Oil from the drain reservoir SHOULD NOT be
reused to avoid clogging.
6.4 Problem Diagnostics
Table 1 lists common problems and possible causes and remedies during the operation.
Table 1. Problem Diagnostics
Symptom Possible Causes Remedies
Low aerosol generation and
or large bubbles in Nebulizer
reservoir.
Clogged impactor
Or clogged nebulizer
Clean Nebulizer. See Figure 5-D p23 and Appendix
B p18.
Clean impactor holes using can-air. (DO NOT
enlarge)
High aerosol generation Overloaded filter
Drain reservoir open
Replace vacuum filter element. Check filter
connection elbows to make sure that all tubes are
tightly connected.
Install drain reservoir.
Calibration Shift See above
Vacuum line leak
Wrong Nebulizer
See above.
Check line, connections, drain reservoir. Calibrate
the Tester with the Nebulizer.
Detector fails to alarm Insufficient aerosol
Defective detector
Unmatched nebulizer
Increase to the maximum concentration.
Switch to a new detector.
Calibrate nebulizer with the Tester
Pressure LED cannot be
adjusted to “green” (“OK”)
(at 15 psig)
Leakage, defective pump
Low battery
Contact Gemini Scientific
Charge battery overnight using charger provided.
Concentration cannot be
adjusted to reach zero
Filter overload
Vacuum line leaks or
pump fails.
Change filter element.
Locate and fix leak. Or contact Gemini.
Pump running, no pressure Major pressure leak Check for leak or pump function.
Dilution air indicator stays at
"Yellow". Or it cannot be
adjusted to "Green".
Low battery
Blockage in hose or wand
Incorrect Diffuser openings
Transducer calibration
shifted
Charge battery overnight or use optional AC Adaptor
Remove hose or wand blockage if present.
"Yellow" - Enlarge some diffuser holes.
"Red" - Tape-close some diffuser holes.
Contact Gemini.