Over-the-range microwave mounted above a stainless electric range
Generic photo: Curtis Adams · Pexels License

Known issue: Whirlpool WMH53520 / WMH73521 over-the-range microwave internal arcing (2016 recall)

In August 2016 Whirlpool recalled about 15,200 Whirlpool microwave hood combinations, models WMH53520 and WMH73521 (CS, CW, CB, CE, CH) with serial numbers TR33500000 to TR34899999, sold January 2014 to April 2016. Internal arcing during use can ignite an internal plastic part. The published remedy was a free replacement microwave. Units of this age are still installed in many homes and rentals.

Cross-checked ~20 min easyBrands: Whirlpool

Before you start

  • Unplug the microwave (or turn off its circuit) and do not run it to reproduce arcing.
  • Do not open the cabinet of a microwave unless trained: the high-voltage capacitor can hold a lethal charge after unplugging.
  • Check the cabinet above for heat or scorch damage.

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Known issue: Whirlpool WMH53520 / WMH73521 over-the-range microwave internal arcing (2016 recall) · OnCall Tech