HTP TIG arc problems

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I recently purchased an HTP (inverter) 160amp TIG machine. I have been using a Miller DialArc (transformer) machine for 25 years. With the HTP I am getting a BRIGHT yellow arc, not blue white, at various times and under varied circumstances....nothing consistent enough to say "that's it". I am using a new bottle of Argon and am an experienced "hobby" welder. This yellow arc completely blots out the entire weld picture and makes it impossible to strike an arc and get a puddle going cuz you can't see anything. Any ideas? Thanks in advance.
Reply:OK, the electrons don't know whether they are HTP or Miller, so it's has nothing the power supply.I'm, guessing it is a shielding problem, or you are contaminating the tungsten by dipping into the weld.As you mentioned, I would look at the gas, there's been several posts where people have been sold a MIG mix for TIG.  Leak check all gas connections, and check the torch including the "O-ring" on the back cap, and the insulator bushing between the nozzle and the torch.  It's counter intuitive, but a leak anywhere in the shield gas line can also allow atmosphere to enter the shield gas stream.Some crap coming off the base metal could cause this, try some nice clean stainless steel, this way you'll see how good your shielding is.  Never heard of tungsten being issue, although I suppose there could be some bad cheapo tungsten out there.What does the tungsten look like after running a "yellow" arc?  Is it clean, bright, and shiny, or black and contaminated.  What does the weld look like.  These clues should help solve your mystery.
Reply:Hmmm.  I ain't heard that one before either, but it does sound gas/shielding related.  Do you still have the dialarc?  if so, try the exact same setup on the dialarc to eliminate a probem with the torch and gas.  What type tungsten are you using?  I only ask because I heard you aren't supposed to use pure with an inverter...not that I know exactly why you arent...just a random passing thought.Smithboy...if it ain't broke, you ain't tryin'.