• In this video, This Old House plumbing and heating contractor Richard Trethewey explains how to create zones in a hot-water heating system.


    1 Turn off cold-water line to boiler; shut the electricity to boiler.
    2 Drain water from boiler, if there’s no floor drain remove water with electric pump.
    3 Cut copper pipe coming from boiler with a tubing cutter.
    4 Use reciprocating saw to cut steel pipe, remove remaining pipe with pipe wrench.
    5 Thread copper adapter into boiler to connect new copper tubing; apply both pipe sealant and Teflon tape to threads of adapter.
    6 Solder together new zone valve assemblies and attach to boiler with solder-less fittings.
    7 Install wireless thermostat in room of new zone; locate thermostat away from direct sunlight or cold drafts, and about 60 inches above the floor.
    8 Install electric control box beside boiler and make wire connections between zone valves and thermostats in each zone.
    9 Turn on cold-water line and electricity to boiler.
    • Difficulty: Hard
      This is a job best left to a licensed heating contractor

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      Tools List

      • propane torch
        Propane torch,
        used to solder zone valves into copper tubing
      • adjustable wrench
        Adjustable wrench
      • needlenose pliers
      • wrench
        Pipe wrench
      • reciprocating saw
        Reciprocating saw,
        used to cut steel pipe
      • tubing cutter
        Tubing cutter
      • drill
        used to mount thermostat

      Shopping List

      1. Electric zone valves,

      used to separate house into different heating zones

      2. Wireless thermostat,

      installed in new zone

      3. Control box,

      connects zone valves to thermostats

      4. Copper tubing

      and assorted fittings

      5. Solder-less copper fittings

      6. Lead-free solder

      7. Flux

      8. Emery cloth 9. Garden hose,

      used to drain water from boiler

      10. Pipe sealant

      11. Teflon tape

      12. Electric pump,

      needed to remove water if there’s no floor drain

      13. Solder-less fitting crimping tool