- No peak for caffeine sample
- No peaks running the gradient test
- Pressure trace does not change with gradient changes for AB and CD
- Pump and system leak tests fail
- Peaks returned with GPV replacement show tailing and lower sensitivity
- Peaks missing again after I2V check valve replacement and primary head rebuild
- Peaks return with removal of sample loop
- Wash of system with phosphoric acid shifts retention times
- ACQUITY UPLC H-Class
Injection valve leaks to waste during injections.
FIX or WORKAROUND
Replace the injection valve cartridge (700005236).
- See section 3.12 in ACQUITY UPLC SM-FTN Overview and Maintenance Information (715005051)
gradient proportioning valve