: Mechanical versions use a 24-hour dial with tappets; digital versions often have sliders or buttons to set "ON" and "OFF" periods.
| Problem | Likely Cause | Fix | |---------|--------------|-----| | Heating on when it should be off | Switch in "Constant" position | Move to "Timed" | | Heating off when tappets are set IN | Switch in "Off" position | Move to "Timed" | | System ignores times completely | Internal motor failed (common) | Replace programmer (Mini Minder obsolete) | | Time drifts or dial not moving | Motor stalled or gears worn | Replace programmer | | Tappets won't stay pushed in | Broken plastic tabs | New programmer needed | potterton mini minder