General Maintenance for the Agilent Flame and Graphite Furnace Atomic Absorption Systems

Answer

This Information Applies To: Agilent Atomic Absorption Spectroscopy Systems (240/280 Series Flame AA and 240/280Z/Zeeman/GTA 120 Graphite Furnace)

Issue:

This article includes recommended maintenance procedures to be performed daily, weekly or annually to ensure optimum performance of the Agilent atomic absorption systems.

Steps to follow:

Schedule of recommended maintenance procedures:

• Daily
  
  • Check that the exhaust system has positive extraction
  • Check the gas supplies
  • Check all hoses and connections for damage, leaks, and deterioration
  • Empty the drain vessel
  • Clean the Instrument panels/surfaces
  • Clean the burner (Flame systems only)
  • Rinse out the spray chamber and liquid trap (Flame systems only)
  • Check the graphite components-shroud, electrode, tube (Furnace/Zeeman systems only)
  • Clean the electrodes (Furnace/Zeeman systems only)
  • Replace the graphite tube if needed (Furnace/Zeeman systems only)
• Weekly
  • Check for O-ring deterioration:
    • Three O-rings inside the burner, spray chamber, and the bung (see Figure 1)
    • Two O-rings that seal the gas inlets to the spray chamber (see Figure 2)
  • Clean the lamp and sample compartment windows (wipe away any buildup)
  • Check the air compressor filter
  • Check the water levels in the recirculating supplies/chiller (Furnace/Zeeman systems only)
• Yearly
  • Arrange for an Agilent service engineer to perform preventative maintenance

Figure 1. Spray chamber O-rings

1. O-ring on burner assembly   2. O-ring inside the spray chamber   3. O-ring inside the bung

Figure 2:   1. O-rings (x2) that seal the gas inlets to the spray chamber

Cleaning

• Instrument Surfaces: 

Tips: Clean contamination immediately using the approved laboratory procedures. If there is contamination inside the instrument, immediately turn off the instrument and call your Agilent representative

1.  Switch off the instrument and allow it to cool.
2.  Remove any hardware present in the sample compartment (see the appropriate instructions in the User’s Guide and the SpectrAA Help if necessary).
3.  Using a cloth dampened with water, clean the sample compartment, instrument cover, and chimney. On Flame systems, also clean the front panel and flame shield. If necessary, use a mild detergent to clean the cover. Do NOT use an abrasive cleaner. When analyzing biological samples, wipe the instrument with chlorhexidine in 95% ethanol.

• Windows:

1.  Clean the sample compartment windows and the lamp compartment window with a gentle stream of filtered air, or a puffer brush, like those used to clean camera lenses.
2.  If the windows are dirty, wipe them using a lens cleaning paper held between tweezers and dampened with a 50% ethanol/water solution.

• Filters:

1.  Check the filter in the air compressor supply line and clean if necessary (instructions are included with the filter).

• Gas Cylinders:

1.  Change gas cylinders according to the instructions supplied by the manufacturer.
2.  When changing gas cylinders:
   1. Inspect all gas supply pipes and hoses. Replace any hose showing signs of damage or deterioration.
   2. Test all connections for leaks using a commercial leak testing solution, a mild dish washing soap solution, or an electronic leak detector.
   3. Test the operation of all regulators.
   4. Ensure that shutoff valves are correctly working.

Caution: Preventing flashbacks: Instrument and consumable maintenance is important to prevent flashbacks or unexpected flame events. See the Safety section on Page 22 of the instrument User's Guide for detailed information on how to prevent flashbacks, and Page 24 for what to do in the event of a flashback. Agilent 240/280 Series AA (including Zeeman) User's Guide

Fuses

Warning: Fire, Hot Surface, and Explosion Hazards: To prevent reduced safety protection or unwanted fusing, always ensure that the code on the fuse cap matches the values shown in the tables next to the fuse holders.

The spectrometer contains two operator-accessible fuses located at the back of the instrument. To replace a fuse, disconnect the instrument from the power supply, and replace blown fuses with one of the type and rating indicated next to the fuses.

Tips: Always check the information printed on the back of the instrument for the correct fuse type. The fuses have a code marked on the cap (for example, TF2AH250V). This refers to the fuse characteristic ('T'=time lag, 'F'=fast acting), the current rating ('x' amperes), the breaking capacity ('H'=heavy, 'L'=low), and the voltage rating ('y' volts). This code MUST correspond to the code appearing next to the fuse holders.

• To check a fuse:

1.  Disconnect the instrument from the main power supply (i.e. unplug the power cord)
2.  Remove the fuse holder, located to the right of the main input connection. Using a flat bladed screw driver, lever the fuse holder from the instrument.
3.  Check that the fuses are the correct type and not damaged. If needed, replace the fuses with the correct replacement type.
4.  Replace the fuse holder in the instrument, and reconnect the instrument to the main power supply.

• If a fuse repeatedly blows, it may indicate other problems with your Agilent AA instrument. If this happens, contact Agilent Technical Support and arrange for a service.

Learn how to effectively operate your Atomic Absorption System: Agilent 240/280 Series AA (including Zeeman) User's Guide user manual on Agilent.com