• In this video, This Old House plumbing and heating contractor Richard Trethewey explains how to replace a water heater.


    1. Turn off cold-water pipe leading into the water heater.
    2. Shut off the gas supply to the heater.
    3. Drain water from the heater using a garden hose.
    4. Use a tubing cutter to sever the cold- and hot-water pipes connected to the heater.
    5. Disconnect the union that connects the gas pipe to the heater.
    6. Remove old water heater.
    7. Set new heater on top of blocks.
    8. Attach exhaust flue to top of heater.
    9. Solder new copper pipe to connect heater to cold- and hot-water pipes.
    10. Reconnect gas line to heater.
    11. Install vacuum valve to top of heater; wrap threads with Teflon tape, tighten with pliers.
    12. Turn on cold water to fill tank.
    See products and services in this episode
    • Difficulty: Moderate to hard
      Requires basic plumbing skills and the strength to wrestle out the old heater, and carry in the new one

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      Video Directory

      Selected Topic/Section

      Tools List

      • propane torch
        Propane torch
      • tubing cutter
        Tubing cutter,
        used to cut copper tubing
      • needlenose pliers
        used to install vacuum valve
      • hand truck
        Hand truck,
        used to remove old water heater, and to bring in new heater

      Shopping List

      1. Water heater

      2. Copper tubing and assorted fittings

      3. Vacuum valve

      4. Emery cloth
      used to clean outside of pipe ends prior to soldering 5. Flux

      6. Lead-free solder

      7. Garden hose
      used to drain water from heater

      8. Teflon tape
      used on threads of vacuum valve