How could we solve error 1118 at 7700 series ICP-MS?

Question

Hello, we are using 7700X series ICP-MS from 2013 . A few days ago we had an error message (Error 1118) .When our instrument is changing from Standby mode to Analysis mode vacuum pressure (IF/BK) can not drop below the lower limit within the prescribed time. (The lowest limit we got was 530 kPa) 
 From ICP-MS Mass Hunter Help we searched the error and try to figure out the problem. It says that the list below could cause the problem. 
 
 "Check the vacuum pressure (IF/BK) for the following possible issues. 
 A drop of water was introduced into the vacuum chamber. 
 The diameter of the hole in the sampling cone is too big. 
 The seal of the sampling cone is incomplete (Defective gasket). 
 The plasma is too far from the sampling cone. 
 The power of the foreline pump is not connected or the breaker is OFF. 
 The foreline pump oil level is low or the oil is dirty. 
 The vacuum tubing has failed (the tubing is off, or a leak is caused by an incomplete seal such as a pin hole or a defective O-ring). 
 There is a fault in the Pirani gauge (IF/BK) or the Connection PCA." 
 
 We changed our skimmer cone, sampling cone and graphite gasket. 
 We tried a different Edward pump as well as two new Agilent MS40-s pumps. 
 We changed the hoses from and to the vacuum pump as well as the one to the Pirani gauge. 
 We changed the Pirani gauge itself. 
 We have changed the o-ring on the inlet of the vacuum pump. 
 IF/BK vacuum manifold was renewed.

We still have the same error message. What should we check more? 
 One thing we haven&rsquo;t checked that is on the list of possible issues is If the plasma is too far from the sampling cone. what can we do in that case??

CGS · Answer

Hello nafu 
 
 Please, contact with your Support Center in order to help you 
 
 Thanks 
 Regards

Tom Herzog · Answer

When you run startup, does it use the Standard Tune or User Tune? In the new D rev of software (5.X) you can go to Startup/Startup Configuration and just above the Hardware settings table select Configure ignition sequence. For C rev (4.X) click the narrow menu bar next to the Plasma button and select Configure Ignition Sequence. If User Tune is selected, go to User Tune and check what RF power reads. It is typically 1550W, if much lower you are starting up in cool plasma, and this may be adding to the issue. The higher the plasma power, the denser the plasma ball which gives a better seal. Try running startup with Standard Tune and see if it will get to Analysis mode. If already set to Standard tune. 
 The engineer should be able to check the depth using the service diagnostics and a procedure in the service manual. It sounds like your plasma turns on, moves into position, and you can hear the sound of the interface valve open before it turns off and gives the 1118 error? After it goes off, measure from the tip of the torch to the sample cone base it should be ~8mm. If much farther away this could cause the error. 
 You mentioned that you changed the hoses to the pirani gauge, is this the one from the back of the instrument to the IF/BK valve, or from the interface to the IF/BK valve, or both? I have seen where the hose from the interface to the valve will degrade from acid over time and develop a leak. 
 How good is the vacuum in Standby mode from sitting overnight? What does the IF/BK pressure and Analyzer pressure read first thing in the morning? 
 Let us know what you find.