Thermo Scientific EASY-nLC 1200 Troubleshooting And Maintenance Manual page 240

7
Troubleshooting
Troubleshooting a System Blockage
218 EASY-nLC 1200 Troubleshooting & Maintenance Guide
d. Depending on the test results, do one of the following:
• If Test solvent B passes, clean the mixing Tee and if necessary replace it.
• If Test solvent B fails, go to
2. To determine if the blockage is in the solvent line that connects the B flow path to the
mixing Tee, do the following:
a. Disconnect the solvent line from the outlet of flow sensor B.
b. Place valve B in position 1–6 as follows:
i. Press Home > Overview.
ii. Press the valve B icon.
iii. In the Valve B dialog box, press 1–6.
c. Set pump B to deliver 2 µL/min as follows:
i. Press the pump B icon.
ii. In the flow rate box, type 2 µL/min.
iii. Press Start.
iv. Leave the dialog box open.
For more information about the direct controls for the pump, see
Controls" on page
d. Monitor the Pressure readback box for pump B. Then, depending on the
backpressure, do one of the following:
• If the pressure is <20 bar, the solvent line is blocked.
– Place valve B in position 1–2 to release the pressure. Remove the blocked
nanoViper line and replace it with a new nanoViper line. Then, to confirm
that the blockage was in the discarded solvent line, repeat the Back Pressure
script with the Test Solvent B check box selected.
• If the pressure is >20 bar, keep pump B running and go to
3. To determine if flow sensor B is blocked, do the following:
a. Disconnect the solvent line from the inlet of flow sensor B, and monitor the pressure.
b. Depending on the pressure, do one of the following:
• If the pressure is <20 bar, flow sensor B is blocked. Replace it as described in
"Replacing a Flow Sensor"
• If the pressure is >20 bar, keep pump B running and go to
4. To determine if the line that connects valve B to flow sensor B is blocked, do the
following:
a. Disconnect the line from port 6 of valve B, and monitor the pressure.
step 2.
166.
on page 92.
"Using the Pump
step 3.
step 4.
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