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Saddle Valve
(Also known as a “tap-a-line” valve)

A saddle valve is a compact plumbing device designed to create a secondary outlet from an existing tubing line or pipe—typically for supplying water to appliances such as ice makers, humidifiers, or reverse osmosis systems.

Description:

  • It is named for the way it “saddles” the pipe, clamping onto it like a saddle on a horse.
  • The valve is usually attached to a copper, PVC, or steel pipe via a clamp or silver brazing.
  • A sharp piercing needle or spike is integrated into the valve mechanism. When the handle is turned, the spike punctures the pipe wall, creating a small opening that allows fluid (often water) to flow into the new outlet.
  • In some models, a hole must be drilled prior to installation rather than using the piercing spike.

Key Features:

  • Simple and low-cost installation, requiring no pipe cutting or soldering.
  • Common in DIY home plumbing projects.
  • Typically used with low-pressure systems and small-diameter tubing (e.g., 1/4″ supply lines).
  • Not recommended for high-demand or permanent applications, as it may leak or clog over time.

Typical Applications:

  • Supplying water to:
    • Refrigerator ice makers
    • Evaporative coolers
    • Undersink filtration systems
    • Aquarium water systems

Note:

Many building codes now discourage or prohibit the use of saddle valves in favor of more durable alternatives like tee fittings with shut-off valves, due to potential long-term reliability issues.

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