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Fluctuating pressure, high delta psi with Alliance 2695 SM or 1515 pump - WKB21017

Article number: 21017

SYMPTOMS

  • Fluctuating pressure
  • High delta psi (400 psi)
  • Replacing the Solvent Bottle Filter, 1/pkg (700003615]) does not solve the problem
  • Solvent present on pump head body (outside of seals)
  • Solvent leak seen at base of pump head

ENVIRONMENT

  • Alliance HPLC System
  • 2695 Separations Module
  • 1515 Isocratic HPLC Pump
  • 1525 Binary HPLC Pump
  • 515 HPLC Pump

CAUSE

Faulty plunger seals

FIX or WORKAROUND

  1. Remove the solvent line filter from the mobile phase bottle.
  2. Using two 5/16-inch wrenches, disconnect the tubing that goes into the inlet and outlet check valves.
  3. Using a 5/32-inch hex wrench, remove the two support screws that hold the pump head onto the support plate.
  4. Carefully slide the pump head off the pump.
  5. Use a non-metallic tool to remove the clear seal and washer from the pump head, being careful not to scratch the pump head.

clear-seal.png

  1. Place a new washer and plunger seal on the pump head seal orifice:
  • 2695: Plunger Seals Replacement Kit (Std-Yellow) 2/Pkg (WAT270938])
  • 1515: Clear-100™ Plunger Seal (WAT022934])
  1. Wet the new seal with methanol, and then, with a gloved hand, use the flat part of your thumb to press the seal into the pump head.
  2. Carefully install the pump head onto the plunger support and fasten it with the two 5/32-inch hex screws. Tighten evenly until both are tight, to prevent excessive torque on the plunger.
  3. Prime the pump with methanol.
  4. Using a restriction device such as an old column, pressurize the seals to at least 3000 psi for 10 minutes.
  5. Confirm that the pressure is stable.

ADDITIONAL INFORMATION

Also replace the plunger if signs of wear or damage are present.

1515 User's Guide

id21017, 1515, 1525, 1525U, 1525UIVD, 2690, 2690D, 2690DUPGD, 2690UP, 2695, 2695D, 2695DE, 2695DEB, 2695DUP, 2695E, 2695EB, 2695INERT, 2695UP, 515, A-10SSM, ALLCOLCLR, ALLCOLHTR, ALLCOLHTRB, checkvalve, eluent, pressure fluctuation, pressure ripple

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