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Thermo Fisher Scientific

Error 2204


Unable to ignite the plasma because of an error 2204 (Water or Exhaust flow interlock)


  • iCAP 6000
  • iCAP 7000


  • If the plasma will not ignite because of an Error 2204, problems due to the water solenoid can be determined by watching for a pressure drop in the Thermoflex 900/1400 chiller after plasma ignition by pressing down on the Thermoflex LCD panel.
  • If the pressure does not drop after plasma ignition, then it is recommended to replace the water solenoid.
  • If for any reason, the water solenoid is on backorder, or the customer is in an urgency to begin their sample analysis; the following steps below can be used to bypass the water solenoid.
  • It is not recommended to leave the water solenoid bypassed as it can cause issues with premature RF generator failure.
  1. Detach the contract wires, and remove the three Phillips head screws. See figure 1.

Figure 1

figure 1.png

  1. Pull off the head of the Water Solenoid. See figure 2.

Figure 2

figure 2.png

  1. Pull apart the middle of the Water Solenoid exposing the spring. See figures 3a and 3b.

Figure 3a

figure 3a.png

Figure 3b

figure 3b.png

  1. Remove the plunger from the middle of the Water Solenoid.
  2. Reattach middle of the Water Solenoid to the bottom without the plunger.
  3. Attach the water solenoid head, and tighten the Phillips head screws.
  4. Attach the Water Solenoid contact wires, and ignite the plasma.
  5. If the 2204 error persists and the pressure in the Thermoflex 900/1400 water chiller does not drop, then there is a significant clog in the water flow.


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