Esab 550. I had cut three holes in 1/4" plate when it just stopped cutting in
mid-stream. No spark. I checked the consumables, they're all new.

I still get air when I hit the trigger. The overheat light isn't on. It still
doesn't work the next day.

I checked continuity of the power cable with an ohm meter and it has continuity,
almost zero resistance. Is there some other way to test it? Could it have
continuity at rest but fail under load?

The trigger wires obviously have continuity because the trigger still works the
solenoid valve to supply air to the torch.

It just won't cut anything.

The book suggests replacing the HF unit. How can I test the HF unit and what
kind of money are we talking about to replace it?

--
Jack