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DIY guideWater heater

Inspect and replace the water heater anode rod

Turn the heat and the water off, let some water out, unscrew the rod on top and see how much is left. A rod worn to its core gets replaced, and the tank lasts longer.

  • 1 hr to 2 hr
  • 9 steps
  • Every step animated
Inspect and replace the water heater anode rod: the animation’s first picture

9 steps

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  1. Electric: switch off the water heater's breaker. Gas: turn the control knob to Pilot or Vacation. Let the water cool for a few hours.

    The water inside can scald. Let it cool first.

  2. Turn the cold water valve on the pipe at the top of the heater clockwise until it stops.

  3. Open a hot tap, then run a few buckets out of the drain valve at the bottom, so the water sits below the top.

  4. Find the hex head on top of the heater. It may be under a plastic cap or a little insulation.

  5. Fit a socket on a long bar onto the hex and turn it counterclockwise while someone steadies the tank.

    If it won't move with steady force, stop. Forcing it can twist the tank's fittings.

  6. Lift it out. Worn to a thin wire, or half gone: replace it. Coated but thick all along: put it back.

  7. Wrap its threads with thread tape, lower it in and tighten it firmly. No room above? Use a rod with joints.

  8. Open the cold valve with the hot tap still open. When water runs without sputtering, close the tap and check the hex for drips. Then turn the heat back on.

    Never turn an electric heater on while the tank is empty.

  9. If the hex won't turn, the rod is part of the hot pipe, or the tank leaks: close the cold valve and ask Handyman for a plumber.

What you need

  • A socket that fits the rod's hex, and a long bar for it
  • A new anode rod the length of the old one (jointed if there's little room above)
  • Thread tape
  • A garden hose and a bucket
  • Work gloves

Call a pro if

  • The hex won't turn with steady force
  • The rod is part of the hot water pipe on top
  • Water leaks from the tank or round the hex
  • You smell gas: leave the house and call the gas utility from outside

Handyman says: Won't budge? I'll find you a plumber.

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