ICP-OES Torch Overheating

Answer

This Information Applies To: Agilent ICP-OES Systems (700 Series, 5000 series)

Issue 

If any yellow or orange coloration on any part of the torch is observed (not due to the sample being presented or recently run) or if the torch appears to be visibly melting, the torch is overheating.  

Figure 1. Example of damaged torch

Steps to Follow

Caution: To prevent damage to the instrument, do not use the torch if it is damaged

Warning: The torch and torch compartment become hot during instrument operation and remain so for some time after the plasma has been switched off. Allow the plasma compartment to cool before accessing the plasma compartment. Allow the torch to cool before touching the outer tube or attempting to dismantle the torch.

1. Perform the torch cleaning procedure as soon as any discoloration appears on the outer tube of the torch.
2. Check that the torch is inserted correctly into the ICP-OES. The torch must be concentric within the induction coil; no part of the torch must touch the coil. see Figure 2.

Figure 2. 1 Torch, 2 Induction coil 

3. Ensure that argon is flowing from the nebulizer into the spray chamber and the torch. Look for a mist in the spray chamber. See Figure 3. Check for kinks in the nebulizer gas tubing and replace if necessary.
4. Check for correct gas pressure from the argon source.
5. Check the RF power and plasma gas flow settings. Using high RF power with low plasma gas flows will result in the torch overheating. Increase the plasma gas flow and/or reduce the RF power.

Figure 3. 1 Mist in spray chamber

Learn how to effectively maintain and troubleshoot your Agilent ICP-OES Instrument: Guidelines for Trouble Shooting and Maintenance of ICP-OES Systems