CETAC Aridus II, Operator'S Manual

Page: 46 / 62

Aridus II™ Operator’s Manual
46
High elemental oxide levels
•
High levels of oxides are caused by non-optimum sweep gas flow rate or
solids buildup on the membrane. Repeat the sweep gas optimization
procedure. If this does not correct the problem, the membrane may
require cleaning. Refer to the rinsing procedure. Under normal usage
(dilute acid samples), the membrane should be thoroughly flushed
approximately every three months.
•
Non-volatile membrane build-up. Make certain that solvents are not
analyzed which have a boiling point > 160°C. These solvents will not be
removed from the membrane and will require that the membrane be
rinsed and the Aridus II
™
re-optimized.
Excessive nitrogen-containing polyatomic ion interferences
• Decrease nitrogen flow.
Nebulizer self-aspiration stops
•
The nebulizer capillary may be obstructed. Use the C-Flow flush kit to
help remove the obstruction. Refer to "Maintaining the Aridus II™"
beginning on page 31.
•
Make certain that the nebulizer gas is turned on, the nebulizer gas line is
leak-free and the proper amount of gas pressure (at least 60 psi, 420 kPa,
4.2 bar) is being delivered to the C-Flow PFA nebulizer.
•
The nebulizer capillary may be irreversibly clogged or damaged. Contact
CETAC Technologies for a replacement nebulizer.
Plasma Problems
Plasma flickers excessively or is unstable.
•
The most likely cause of plasma instability is a leak in the Aridus II
™
nebulizer / membrane system. Check all gas line connections. Make sure
all connections are tight and correct. Very high gas flow may also cause
plasma instability. Refer to “ System Optimization ” in Chapter 4, “ Verifying
Installation.