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Backflow preventer dripping or spitting, failed test or cross-connection.

A homeowner or trained tech can read tags, sketch connections and log pressure, while testing or rebuilding a backflow device goes to a credentialed backflow tester where the local water authority requires one, and installing or replacing it to a licensed plumber.

Customers put it like this

  • The backflow preventer is leaking
  • We got a letter saying our backflow test failed
  • The sprinkler system is hooked to our drinking water
  • The tap water tastes like antifreeze
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Stop first if

  • The tap water smells or tastes of chemicals, antifreeze or sewage, or turns colored after a pressure dropStop drinking it and call the water supplier. Use bottled water until they say it is safe.
  • Someone who drank the water has cramps, diarrhea or a flu-like illnessStop drinking it, get medical advice and call the water supplier.
  • Water is pouring from the backflow device, or has reached a panel, outlets or a pumpStay out of the water and call a licensed plumber, and an electrician for wet electrical gear. Close the main only if it can be done without risk.
  • A relief valve or its pipe has been capped or plugged on a working heater or boilerTreat it as an explosion risk. Keep people clear and call a licensed plumber now.
01

Ask on the call

6

Homeowner? These are the questions a good technician will ask you. Having the answers ready makes the first visit count.

  1. What did you notice: water from the device, a test notice, or an odd taste, smell or color?
  2. When did it start, and was there a shutoff, main break, street work or boiler service around then?
  3. What does the water feed: a boiler or heating loop, a solar water heater, irrigation, hoses, a well or a filter system?
  4. Is there a backflow device at each of those, and what date and result are on its test tag?
  5. Is this a home or a business, and did the water supplier send a notice or a test deadline?
  6. What fluid is in the heating or solar loop, and is it labeled?
02

Bring

5
  • Hose bibb gauge that records over a day
  • Flashlight and camera
  • Bucket and towels
  • Sketch pad
  • The supplier's notice and last test report
03

Check on site

7
  1. Line up when it started with any shutoff, main break, street work, fire use or boiler service. Gather test tags, past reports and the supplier's notice.
  2. Walk each outlet the water feeds: hose bibbs, irrigation, boiler room, laundry. Sketch each, and note any hose or spray that can sit below a rim.
  3. Read each device's type, model and test tag, and look for piping around it. A tag is a record, not a pass, and a check built into the meter can hide from view.
  4. If the device drips, watch the relief port without touching it, and never plug or cap it. Note where the water goes and if the port could ever sit under water.
  5. Where it cannot have frozen, log inlet pressure over quiet hours before any rebuild. Drips with pressure dips point toward supply swings, steady ones toward a fouled check.
  6. At a heating, solar or glycol loop, photograph the fluid label and the exchanger plate showing single or double wall. Ask the supplier or a lab about a sample.
  7. A credentialed backflow tester does any test or rebuild where the water authority requires one. A licensed plumber installs or replaces the device.
04

Keep on the record

5
  • Device type, model, size and serial from its tag, with photos
  • Test tag date and result, and the supplier's notice or deadline
  • Sketch of each connection the water feeds and what protects it
  • Inlet pressure log set against the times the device dripped
  • Exchanger nameplate and loop fluid label photos

General guidance for a qualified person, not a finding about any home. The person on site decides.