No Pressure or Pressure Lower than anticipated

No Pressure or Pressure Lower than anticipated

                     

What you Expect.                                 What you got

Disease	Medicine
Leak	Check for loose fittings Check pump for leaks, salts and noise Check seals
Mobile phase interrupted	Check reservoirs. Check position of the inlet tubing Check loop for obstruction or air Check degasing of mobile phase Check compatibility of the mobile phase components
Air trapped in pump	Check flow disconnect column and prime pump Flush system with 100% methanol or iso propanol Contact servicing if necessary
Worn pump seals	Replace seals Check pistons and replace if necessary

Higher Pressure than anticipated

  What you Expect.                                 What you got

Disease	Medicine
Pump, injector, tubing	Disconnect column, run pump at 25 mL/min: Is the pressure minimal? Go to next step If pressure still high check systematically from detector to pump for obstruction
Obstructed column or guard	If guard column is obstructed, replace it If the analytical column is obstructed reverse it and flush disconnected from the detector. Use adequate restoration procedures Change inlet frit Replace de column

            

reference: 

Prof. Dr. H.J. Chaves das Neves

Universidade Nova de Lisboa