Check the piston head, especially if you have not changed oil
I'm having a lot of problems with the HF 90234 model. First, the amperage wasn't sufficient to get it started. That would trip the onboard breaker. I moved it to another circuit and that solved the starting problem.
Now, it trips before getting to max-pressure. I'm running a plasma cutter, so I need plenty of reliable airflow.
I disassembled the piston head to see if it was clogged with residue. Yup. Thick and gooey. I pulled it all apart and re-assembled without difficulty. Also changed the oil. I also read that I should have changed the oil soon after running it for a few weeks. So, that would have probably minimized the build-up.
But, now it is still not reaching max-pressure before the onboard breaker trips. There's plenty of airflow, and the head only reaches 150 Deg F.
Any ideas why it's tripping? Maybe the motor is overheating? Maybe a bad breaker?