ACQUITY SM-FTN system over pressure - WKB6394

SYMPTOMS

• ACQUITY System with SM-FTN reports HW over pressure on solvent manager during run
• Needle seal readiness test passes with high pressure difference (for example, 1000 psi at 0.1 mL/min) 
• High pressure at low flow rate (for example, 0.1 mL/min) with the column disconnected going directly to waste

ENVIRONMENT

• ACQUITY UPLC I-Class SM-FTN
• ACQUITY UPLC H-Class SM-FTN
• ACQUITY Premier System

CAUSE

Debris or particulates were forced into the needle seat port or needle seal, causing a blockage and system overpressure. Inspect sample vials and needle wash for particulates or growth. A blockage in this area is nearly always introduced from the injector area. 

FIX or WORKAROUND

  ** Try a reverse flow and flush the seat port first to unclog if it doesn't work then proceed with replacing these parts ** - see WKB115842

• Replace the needle seal (Vespel with anti-rot seat, part 405011492). 
• Replace the seat port if required.
• Ensure that pressure is back to normal and that values are as expected.
• Run "Characterize Needle Seal".
• Run "Needle Seal Readiness Test" as a leak test.

ADDITIONAL INFORMATION

Seat port assembly parts:

• I-Class 0.003 ID: 700006056
• H-Class 0.004 ID:  700005234
• H-Class Bio 0.004 ID: 700005682
• Premier: HPS part 700012823

Before replacing any part, determine whether the injection valve or needle is clogged. See article WKB19544.