Thermo Scientific EASY-nLC 1200 Troubleshooting And Maintenance Manual page 236

7
Troubleshooting
Troubleshooting a System Blockage
214 EASY-nLC 1200 Troubleshooting & Maintenance Guide
4. To determine if valve S is partially or totally blocked, do the following:
a. Disconnect the mixing Tee line from port 4 of valve S.
b. Depending on the backpressure, do one of the following:
• If the pressure is below the threshold of 90 bar, valve S is partially or totally
blocked. Discontinue this troubleshooting procedure and contact product
support.
• If the pressure is above the threshold, reconnect the mixing Tee line to port 4 of
valve S, and go to
5. To determine if the line that connects valve S to the mixing Tee is blocked, do the
following:
a. Disconnect the line from the mixing Tee.
b. Depending on the backpressure, do one of the following:
• If the pressure is below the threshold of 65 bar, the line that connects the mixing
Tee to valve S is blocked. Replace it.
• If the pressure is above the threshold of 65 bar, reconnect the line to the mixing
Tee, and go to
6. To determine if the mixing Tee is blocked, do the following:
a. Disconnect the line that exits flow sensor A from the mixing Tee.
b. Depending on the backpressure, do one of the following:
• If the pressure is below the threshold of 65 bar, the mixing Tee is blocked. Clean
the mixing Tee, or if necessary replace it.
• If the pressure is above the threshold of 65 bar, reconnect the line to the mixing
Tee, and go to
7. To determine if the line that connects the mixing Tee to flow sensor A is blocked, do the
following:
a. Disconnect the line from the outlet of flow sensor A.
b. Depending on the backpressure, do one of the following:
• If the pressure is <20 bar, the line that connects the mixing Tee to flow sensor A
is blocked. Replace it with a new solvent line.
• If the pressure is >20 bar, reconnect the line to flow sensor A, and go to
step 5.
step 6.
step 7.
step 8.
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