Why old valves cause trouble

Many older homes still have gate valves, the kind with a round handle that turns many times. Inside, a wedge slides down to stop the flow. After years without use, mineral buildup and corrosion can freeze the stem, or the wedge can come loose so the handle turns but water keeps running. Packing around the stem can also begin to drip once a stiff valve is finally moved.

Fixture shutoffs under sinks and behind toilets age the same way. Finding out that a valve does not work in the middle of a leak is the worst time to learn it.

Finding the main shutoff

  1. Follow the line from the meter

    Water service usually runs from the meter near the street toward the building. The house shutoff is often where the line enters or rises near the foundation.

  2. Check common spots

    Look near the front hose bib, in the garage, in the crawlspace near the front wall, or near the water heater.

  3. Note the valve type

    A round wheel handle is usually a gate valve; a lever that turns a quarter turn is usually a ball valve.

  4. Label it

    Tag the valve and tell everyone in the household or building where it is.

Gate valves versus ball valves

Older gate valve

  • Multi-turn wheel handle
  • Slow to close in an emergency
  • Can seize or fail to seal after years unused
  • Packing may drip once moved
  • Common in older plumbing

Quarter-turn ball valve

  • Lever handle shows open or closed at a glance
  • Closes quickly
  • Generally reliable when exercised now and then
  • Often installed during repiping or valve replacement
  • Easy for anyone in the household to use

When replacing valves makes sense

  • The main valve will not close fully or leaks when moved
  • Fixture stops are corroded, frozen or dripping
  • You are repiping, remodeling or replacing a water heater
  • Several people need to be able to shut water off quickly, such as in a rental
  • The valve is buried or hard to reach and could be relocated

Questions to ask a plumber

  1. Can you test my main shutoff and fixture stops while you are here?
  2. If the main valve fails while being replaced, what is the plan?
  3. Would you replace the main with a quarter-turn ball valve?
  4. Should the old galvanized nipples at the valve be replaced too?

Common questions

How often should I exercise my shutoff valves?

Many plumbers suggest turning them occasionally so they do not seize, but old gate valves can start leaking when moved. Ask a plumber to check them first if they have not been used in years.

Can I shut off water at the meter myself?

The meter and street side of the service belong to the water utility. Check with the City of Fullerton about their rules before operating meter-side valves.

My valve handle turns but water keeps flowing. Why?

In a gate valve that often means the stem has separated from the internal wedge. The valve needs replacement.

General information for Downtown Fullerton, not a quote or professional advice. In an emergency, call 911.