TIG Gas And Tungsten Matrix

This annex is for TIG complaints that are often blamed on the power source when the actual fault is in the gas path, tungsten condition, torch front end, or control-mode setup around those items.

Use it with TIG and TIG-capable guides in this library across:

Lincoln Electric
Miller
Fronius
ESAB
Hobart
PrimeWeld
Everlast
Eastwood
Harbor Freight
YesWelder

Core rule

If stick works but TIG does not, keep the diagnosis on torch, gas, remote, tungsten, and clamp first.

Symptom matrix

Symptom	Most likely external TIG branch	High-value first move
No TIG start	remote mismatch, gas path issue, bad clamp, torch path	simplify to known-good DC TIG baseline and verify remote mode
Tungsten contaminates immediately	wrong polarity or process, dirty work, poor gas coverage	confirm mode, regrind tungsten, verify gas flow
Arc wanders or sputters	poor gas coverage, contaminated tungsten, bad clamp	inspect front end, clamp, and gas delivery
Aluminum arc lacks cleaning action	AC settings drift, dirty aluminum, weak clamp or gas coverage	reset AC baseline and clean coupon
Good start but poor finish crater or discoloration	bad post-flow, hot tungsten, gas leak	inspect gas path and post-flow behavior

Gas-path checklist

Verify cylinder contents and regulator or flowmeter setup.
Confirm actual flow, not just that the gauge moved earlier.
Inspect hose path, torch fittings, back cap, cup, collet body, and any gas lens.
If one torch package fails and another works, keep the diagnosis on the torch package.

Tungsten checklist

Verify tungsten type and diameter match the mode and amperage.
Regrind or replace contaminated tungsten immediately.
Confirm the machine is in the correct polarity or AC mode for the material.
Do not interpret instant contamination as a machine failure until polarity, work cleanliness, and gas path are proven.

By machine class

Premium AC/DC TIG platforms

Aspect 230 AC/DC, Dynasty 210, iWave, Square Wave TIG 200, and similar units are highly sensitive to parameter drift layered on top of gas or tungsten issues.
Reset AC balance, frequency, and pulse before broadening the diagnosis.

Transformer TIG platforms

Precision TIG 225, Syncrowave 212, and similar units still produce many remote, gas, and tungsten complaints before true internal failure.
If stick is healthy, keep the first branch out of the main power section.

TIG-capable multiprocess machines

Multimatic 220 AC/DC, POWER MIG 210 MP, POWER MIG 215 MPi, Rebel family, and similar machines often fail in the TIG branch because the machine was not fully transitioned from MIG or stick.
Verify process change, torch type, gas path, and remote method before any deeper diagnosis.

Common false diagnoses

"HF/start circuit is bad" when the remote mode is wrong
"machine is unstable" when the tungsten is contaminated
"AC section is bad" when aluminum cleaning or gas coverage is poor

Escalate sooner when

TIG remains absent with known-good torch, gas, clamp, tungsten, and remote state
both TIG and stick outputs are abnormal on the same machine
the symptom persists from a cold restart with simplified baseline setup

Source posture

This annex is synthesized from the TIG and TIG-capable model guides in this repository.
Exact tungsten type, gas flow range, and remote setup should still be confirmed in the affected machine's manual.