Carpet Pro Thermal Reset - CPU1/CPU1T Upright

Part B333-0400B is the protective switch that shuts the motor down before heat buildup damages it, used across the Carpet Pro CPU1, CPU1T, CPU1QD, CPU2, CPU3N, CPU3QD, CPU4N, CPU4T and the CMP3 series.

Titan owners will find it listed for the TC6000, TC6000.2 and T4000.2, Powr-Flite carries it for its backpack line as the BP6S, BP6P, BP10S and BP10P, the Maytag M700 uses it too, and so does the Clean Max CMPSQD along with a run of Fuller Brush numbers: FBPHD2T, FBPHD2, FBP14PW, FBMMPWCF4, FBHD1T and FBHD1. This many nameplates share one reset switch because the machines underneath them are built on a common platform, badged differently for different sellers.

Wired into the motor circuit, the reset opens once it passes its set temperature and closes again as things cool back down. Working correctly, it produces a fairly recognizable pattern: the vacuum stops mid-task and comes back to life only after it has sat idle long enough to cool off. Actual overheating from a dirty filter, an overstuffed bag, or a brush roll jammed with debris can trigger that same pattern, so ruling those out first matters, because swapping a reset that is doing exactly what it should just puts off the actual repair.

Once airflow checks out clean and the trips keep happening anyway, the switch itself has grown too sensitive, cutting the circuit at a temperature the motor could otherwise handle without issue.

• Part: B333-0400B, thermal reset switch
• Fits: Titan T4000.2, TC6000, TC6000.2, Powr-Flite BP6S, BP6P, BP10S, BP10P, Maytag M700, Clean Max CMPSQD, Fuller Brush FBPHD2T, FBPHD2, FBP14PW, FBMMPWCF4, FBHD1T, FBHD1, Carpet Pro CPU1, CPU1T, CPU1QD, CPU2, CPU3N, CPU3QD, CPU4N, CPU4T, CMP3N, CMP3QD, CMP3T
• Function: cuts power to the motor if it overheats, and resets once it cools
• Replace when: the machine trips repeatedly with clear airflow and no clogs to explain the heat
• Rule out first: a clogged filter, full bag, or jammed brush roll, since a healthy reset trips correctly on those too