Main electrical panel beside a subpanel with its cover removed

240 V appliance missing one leg: dryer no heat, range half-working, water heater cold

On a 120/240 V appliance the 120 V parts (motor, lights, controls) keep working when one hot leg is lost, while the 240 V heaters stop. Measuring the receptacle or terminal block quickly separates a supply problem from an appliance fault.

Cross-checked ~20 min easyBrands: All

Before you start

Measuring 240 V receptacles and terminal blocks is a caution step: CAT III meter, insulated probes, keep fingers behind the probe guards
Do not open the electrical panel cover; reset breakers only from the handle
Breaker replacement and wiring repair are electrician work

Diagnostic steps

Unlock all 7 steps with expected values

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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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