ace2k drives a mains heater, two fans and four motors. A bug that lets the heater run when it should not is a safety problem, not only a software bug. Report it privately, as described below.

Switch the unit off at the mains and unplug it. Do not wait for a reply here.

Report any of these in private, not as a public issue:

• the heater on without both fans, or heating past its limits;
• the heater or a motor still running after the host link is lost, after a STOP or after an error;
• a dryer fault (the thermal cutout, an open or shorted thermistor) that does not stop heating;
• a write to flash outside the ace2k configuration page;
• any way to make the unit unrecoverable through its serial port;
• any frame or command that does any of the above.

A fault you can only reproduce on a modified unit or with a modified image is still worth reporting. Say what was modified.

Use Security → Report a vulnerability on this repository. That opens a private advisory that only the maintainer can see. Include:

• the ace2k version (the release tag, or git describe for a build from source);
• the Klipper version on the host;
• the steps, the commands sent and the Klipper log;
• what the unit did, and what you expected.

This is a one-maintainer project. Expect a first reply within a week. A fix for a confirmed safety problem comes before any other work.

Only the latest release gets fixes. Before you report, check that the problem is still there on the latest release.