Teledyne ACCQPrep HP125, Installation And Operation Manual

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ACCQPrep HP125
Section 6 Maintenance
6-23
6.8.4 Replacement of Ion
Source Housing
1. Place the ion source housing on top of the base plate and
line up with the rear electrical connection. Push down until
source chamber is seated evenly across the base plate.
2. Finger tighten the two thumb screws and finger tighten
the ¼-28 PTFE tube fitting labeled as 'heated desolvation'
on the side of the housing.
6.8.5 Overpressure Error The fluid interface has a pressure transducer to monitor
pressure of the carrier fluid. Since the sample is introduced at
the splitter valve, plugs usually occur between the valve and the
PurIon source sprayer. The most common location for a plug is
within the probe capillary. The occurrence of plugs can be
reduced by using a 0.45 µ syringe filter when injecting samples
for Method Development and Ionization Settings. To trouble-
shoot an overpressure error, complete the following:
• If the error occurs during a run, select C
ONTINUE
W
ITHOUT
PurIon, and the purification can continue
without the PurIon signal or peak detection, but will
rely on any other detector selected such as UV or ELSD.
This allows the run to be completed before trouble-
shooting the plug.
• Use the menu item MS-> Manual control.
• Press the S
TART
C
ARRIER
P
UMP
button.
• Watch the pressure on the ribbon gauge.
• Loosen the fitting at the source inlet. If the pressure
drops, then the source capillary is plugged.
• If there is still an error or the pressure remains high,
then the plug is between that point and the splitter
valve (or the valve itself). Continue to loosen fittings
going back the to the splitter valve until the error is
corrected.
6.8.6 Check Valve Cleaning If the check valves are allowed to dry out after using volatile
salts (e.g., ammonium acetate or ammonium formate), they may
stick and fail to function. Complete the following to clean the
check valves:
1. Remove the inlet and outlet lines from the check valve
holders (Figure 6-34), and then remove the check valve
holders. Pliers may be needed to remove the holders.