Contunuos gas flow when Millermatic 175 is powered on

[Klayton]

Hi, I've got a gas flow issue, as my wife would say. When my Millermatic 175 is powered on using the on/off switch, the shielding gas begins flowing from the gun even though I haven't pressed the trigger. I'm able to stop gas flow by switching the welder off. Everything else seems normal; wire feed, speed, voltage, bead, etc.

Any ideas on how to fix?

[Country Metals]

I had the same problem with a passport. My machine was still under warranty, but they just changed out the valve and it was fine. It could be that the valve is stuck (doubt it but possible), the solenoid is getting low power, solenoid is getting no power (don't know if it is normally opened or closed), or something with the board that cruizer can help with.

[cruizer]

Going to have to tap the back relays on the board, cause one is stuck on and can't remember which one it is,

[Klayton]

Thanks CM and Cruzier,

i reached out to miller tech support and it sounds like I need a new "omron g8p-1c4p-dc24 relay", which looks to be a $3 part vs $400 for a new board. Now I just need to find some tutorials on pc board soldering or find a local shop that do the delicate work for me.

[Klayton]

Anybody know which of the 3 relays controls the gas valve?

[HFD1 Motorsports]

The one that is stuck on sorry I needed to humor myself... ohm out from sol. to relay. with the board plugged in of course

[welding insp.48]

Hi, I've got a gas flow issue, as my wife would say. When my Millermatic 175 is powered on using the on/off switch, the shielding gas begins flowing from the gun even though I haven't pressed the trigger. I'm able to stop gas flow by switching the welder off. Everything else seems normal; wire feed, speed, voltage, bead, etc.

Any ideas on how to fix?

sometimes it maybe a flow meter,however the tigger maybe stuck. that is normal if it's new?not to worry. your miller dealer should have a tigger.
what happens inside the gun there are two wire connectors. sometimes they get get, lose and sticks open.it can stick open,or not work at all.
thus gas fow,and can't shut off.
if that is not the prolem then a valve sticking will do the same thing.such as flow meter or internal.
this is what sometimes happens? fix this is- easy.

[cope]

sometimes it maybe a flow meter,however the tigger maybe stuck. that is normal if it's new?not to worry. your miller dealer should have a tigger.
what happens inside the gun there are two wire connectors. sometimes they get get, lose and sticks open.it can stick open,or not work at all.
thus gas fow,and can't shut off.
if that is not the prolem then a valve sticking will do the same thing.such as flow meter or internal.
this is what sometimes happens? fix this is- easy.

My HH187 did the same thing after sitting unused for a few years. It was the switch, but I removed it and replaced it, and the problem went away. Miller has a manual for the M-10 Mig gun that explains how to disassemble it.