Laundry room with a tank-type water heater beside the washer
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Water heater leaking: fitting or tank?

The key question is whether the water comes from the plumbing (repairable) or the tank itself (replace the heater). Work from the top down: supply connectors, nipples, T&P valve and its pipe, drain valve, element gaskets. Water from the bottom, under the jacket, or a rusty combustion chamber means the tank has failed.

Cross-checked ~30 min easyBrands: All

Before you start

  • Shut off power (verify 0 V) or set the gas control to OFF before inspecting
  • Gas units: look but do not touch the burner, gas valve or flue
  • If the T&P is discharging, do not cap it; see the T&P guide
  • Replacement of a failed tank usually needs a permit and/or licensed plumber

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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