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    Water HeatersIntermediate

    Repair Water Heater Leak

    Time
    60–180 min
    Steps
    6
    Pre-check
    3 items
    Skill
    Intermediate

    Scope

    Find and repair a water heater leak at the T&P valve, drain valve, or fittings, and learn when a leaking tank means the heater must be replaced instead.

    Safety

    Read before starting

    Turn off power/gas and water; beware hot water; depressurize before disassembly.

    Pre-Check

    3 items · complete before you start
    0 / 25 complete

    Steps

    01

    Secure & Inspect

    • Turn OFF power/gas
    • Close cold inlet
    • Dry surfaces; observe fresh water to locate source
    ✅Continue Gate:Leak source identified (top, side, bottom)?
    02

    Top Leaks (connections)

    • Tighten/repair hot/cold connections first while supporting opposing fittings
    • If corrosion is present, drain to below connection level and disconnect hot/cold connectors
    • Remove and replace corroded nipples or dielectric unions with compatible parts
    • Apply thread sealant as required for fitting type, reconnect lines, and verify alignment before final tightening
    03

    Drain Valve Leaks

    • Attempt to reseat by closing firmly
    • Turn OFF power/gas and cold inlet; attach hose and drain tank to below valve level
    • Remove leaking drain valve and install matching replacement with thread sealant on male threads
    • Close valve, refill tank, purge air through a hot faucet, then restore utilities
    • Check valve and nearby fittings for active drips under full pressure
    ✅Continue Gate:Valve replaced/resealed successfully?
    04

    T&P Valve Leaks

    • Test T&P briefly; if it continues to leak, turn OFF power/gas and cold inlet
    • Drain tank below T&P opening, remove discharge tube, and remove old valve
    • Install matching T&P replacement with thread sealant on male threads only, then reconnect discharge tube to code-compliant termination
    • Refill tank, purge air, restore utilities, and verify no drip after heating cycle
    • Verify thermal expansion control (expansion tank)
    ✅Continue Gate:New T&P installed and no dripping?
    05

    Tank Body/Seam Leak

    • If water seeping from jacket or base, plan replacement
    • Use pan and shut off water to mitigate
    ✅Continue Gate:Confirmed tank failure?
    06

    Restore & Verify

    • Open cold inlet; purge air via hot faucet
    • Restore power/gas
    • Monitor for leaks for 30 minutes

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