Field pattern: burning smell when heat first comes on (strip dust burn-off vs real overheating)

Dust that settles on idle strips burns off the first time they heat, usually fading in under an hour. A smell that comes back every cycle, smells like plastic or rubber, or comes with smoke or a tripped breaker is not normal and needs electrical inspection with power off.

Cross-checked ~30 min easyBrands: All

Before you start

Smoke, melting-plastic or electrical smell: shut off at the thermostat and breaker
Strip heat is 240 V: CAUTION
Do not keep resetting a tripped breaker

Diagnostic steps

Unlock all 6 steps with expected values

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