Hello, we are using 7700X series ICP-MS until 2014 . 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 900 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 take maintenance for our vacuum pump from Edwards service. After changing pump oil and finishing maintenance they said vacuum pump performance is ok.
The leak tests for vacuum hoses was done. No problem was found.
IF/BK vacuum manifold was renewed.
We still have the same error message. What should we check more?