Hamilton Beach Short Circuit or Overcurrent on Startup

Microwave trips the household circuit breaker or blows a fuse when starting a cook cycle.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Shorted high-voltage capacitor or diode, Shorted magnetron, Shorted power cord or wiring, Overloaded circuit shared with other appliances

Safety: Do not repeatedly reset a tripping breaker; this indicates a potentially dangerous fault.

Basic checks:

Ensure the microwave is on a dedicated circuit or not sharing with other high-wattage appliances.
Inspect the power cord for damage.

If the breaker trips immediately upon pressing START:

The issue is likely internal (shorted high-voltage component or wiring). Unplug the microwave and do not use it.
Have a qualified technician test the magnetron, capacitor, diode, and internal wiring for shorts and replace defective parts.

Professional Required 5/5

High-Voltage Diode

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