Laundry room with a tank-type water heater beside the washer
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Water heater: water too hot or ECO keeps tripping

On electric tanks overheating usually means a thermostat welded closed or not clamped tightly against the tank, or a grounded element heating outside thermostat control. On gas tanks it is a gas control fault and must be referred. Treat it as a safety call: overheated water is a scald and tank-pressure hazard.

Cross-checked ~45 min moderateBrands: All

Before you start

  • Scald hazard: water at 140°F can burn skin in under 5 seconds
  • Electric: breaker OFF and verify 0 V before handling wiring
  • Gas tanks: turn the control OFF and refer; do not adjust or open the gas valve
  • Never plug or cap the T&P relief valve

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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Water heater: water too hot or ECO keeps tripping · OnCall Tech