Hardware manual

Maintenance 4
Agilent 7500 Series ICP-MS Hardware Manual 4-45
When Blockage Occurs
When blockage is evident please clean following the method below. If washing
with the below method does not clear the blockage, please replace the PFA
concentric nebulizer. When removing the nebulizer from the end cap, please
also inspect the O- ring. If there is any deterioration please replace the O- ring.
1 Disconnect the nebulizer from the end cap.
Refer to the later section “Removing the PFA Concentric Nebulizer”
2 Use the peristaltic pump to wash the nebulizer by pumping pure water
through the nebulizer in the opposite direction.
Reverse the sample tubing on the peripump and place the nebulizer tip in
pure water. Run the peripump for several minutes, allowing it to draw
water through the tip and out the back of the nebulizer. Take care not to
touch the tip of the nebulizer.
If there is memory, clear it by the following special cleaning procedure
outlined below:
1 Please clean the nebulizer either by self- aspiration or pumping,
according to circumstances.
Using a mixture of 5% nitric acid and 5% hydrofluoric acid, self- aspirate for
8 hours at a carrier gas flow rate of 1.0 L/min.
Using a mixture of 5% nitric acid and 5% hydrofluoric acid, pump with the
peripump for 8 hours at more than 170 μL/min.
2 Then rinse for 5 minutes with a flow of pure water.
3 Blow dry with clean, dry air or an inert gas (such as Argon) for 5
minutes.
NOTE
Wear safety glasses and gloves when working with acid.