Plumbing is a system of pipes and fixtures that supply clean water to buildings and remove waste water through drains into sewers underground. It is a vital service that helps keep cities clean and sanitary.
Licensed plumbers are responsible for building codes, ensuring clean drinking water and proper waste management. They also oversee backflow prevention testing and repairs. Contact Holmes Plumbing and Drain for professional help.
Check valves keep media, such as water or gases, flowing in one direction by sealing off the backflow. They can be found in a wide range of industrial applications, including food processing, chemical, water and wastewater treatment, pumping and pipelines, power generation, HVAC and marine and mining. They are also common in residential homes. You can find them in washing machines, garden hose spigots and sprinklers to prevent unsanitary water from siphoning back into the main sanitary water line.
A check valve has a hinged clapper and spring that is normally closed until the pressure downstream is greater than the upstream pressure (known as cracking pressure). This force opens the valve, allowing media to flow through the valve but preventing backflow. The clapper is held in place by the spring until the fluid flows over it, causing the clapper to snap against a rubber seat and seal the valve. Once the clapper is sealed off, it cannot be opened.
While check valves are generally reliable, they can malfunction or fail for a variety of reasons. Common problems include a worn seat seal, lodged debris and water hammer. Water hammer occurs when flow reversal in the downstream pipe causes the check valve to abruptly close, causing a pressure wave that can damage pipes and fittings. Other common failures are a lack of backflow prevention assembly design considerations, improper installation or maintenance and poor material selection.
There are many different types of check valves, from the standard ones available at home improvement stores to ones that have been specifically designed for unique applications. However, there are some descriptive factors that apply to all check valves.
The check valves used in backflow testing are usually made of metal, such as bronze or stainless steel. These are more durable than plastic check valves, but they can also be damaged by high levels of backflow or by sudden changes in pressure.
Since the check valve only allows media to flow in one direction, it is important that it be installed properly. It should always be facing in the direction of flow, and most of them will have an arrow on them to indicate this. The arrow will be on the part of the valve that is closest to the backflow tester. This will allow the tester to see that the check valve is working correctly.
Relief Valve
A pressure relief valve is designed to open at a pre-set pressure level and relieve system pressures when it is overpressured. This prevents the backflow of contaminants into potable water supplies and protects against a possible failure of the check valves.
When the system’s upstream pressure reaches the valve’s set pressure limit, it will crack open and continue to open until the overpressure is relieved. Once the overpressure has dropped to a few psi below the valve’s set pressure, it will close again.
In order to determine the correct set pressure for a relief valve, it is necessary to know what type of check valve is used in the system and what the maximum working pressure is for that type of check valve. Generally, this information can be found on the check valve label or in the manufacturer’s data sheets.
The second step in the test process is to find out what the normal pressure of the system is, or what the pressure is at the point that the first check valve has closed. This is important because if the check valves are not functioning properly and they are in a flow condition, the readings taken during the test will not be accurate.
Once the test has been performed, it is time to set the relief valve opening and closing values. To do this, the user selects the appropriate tab for their valve model and enters Cv or K Factor vs Time data. The user can choose from a linear based on setpoints option or a non-linear (never) profile.
For a time opening transient, the user can enter in a rate limit to restrict how fast the valve can open and close. This is useful if there are limitations in the hardware that can affect how quickly the valve can move or if the valve has too much mass for its inertia to allow it to respond immediately to pressure changes. Users can also set Blowdown Pressure for a non-linear valve model. This will force Impulse to calculate the loss value at the Blowdown Pressure for every time the valve is open.
Test-Cock
A test cock is a small valve used for backflow testing. It draws a little water from the full valve so that you can test the pressure of the backflow preventer without having to take it apart. Generally, you will need two test cocks for backflow testing, and they should be labeled with numbers so that you know which one is which. You can also use them as isolation valves for gauges or other equipment lines.
The main function of a backflow prevention assembly is to limit changes in the direction of water flow and provide pressure relief should those differences exceed safe limits. It does this by incorporating check valves, air inlet valves and relief valves. While most backflow assemblies include test cocks, not all do. Most backflow testing is required annually, but new installs, repairs and relocation of prevention assemblies require testing to ensure that seals and valve seats are intact and not blocked by debris.
During testing, the tester flushes the test kit and opens and closes the bleeder valves on the backflow preventer to ensure that dirt and debris are not being injected into the gauge. This can restrict the elastic element inside the gauge and cause it to give false readings. To minimize this, you should always flush the test cocks after each use.
This 1/8″ lead free test cock is designed for use with Deringer and Magnum backflow devices. It has a full port ball valve design and features a quarter turn screwdriver slot to open or close it. It is also tamper resistant, which reduces the risk of unauthorized re-entry into the backflow device after a repair.
Tester
Backflow testing is an annual service that guarantees your property’s water supply remains clean and free from contaminants. It’s required by New York City law and many other municipalities, including Leesburg, VA. Backflow testing is designed to prevent dirty or contaminated water from being “back-siphoned” into the public water system. This can happen if there is an unexpected drop in the main water line pressure, such as a broken pipe or a fire that uses up a lot of water. A backflow prevention device (BPD) acts as a one-way gate to prevent this from happening.
During backflow testing, your local plumber will use a special test kit to monitor your BPD’s gauges. They’ll also check that your backflow preventer device is working properly by opening and closing its valves. Then, they’ll shut off the water supply to your building for 30 minutes while they watch the gauges. Once they’re done, they’ll turn your water back on and fill out all the necessary paperwork.
Because backflow testing involves monitoring water pressure, it’s essential to have the right equipment for the job. Backflow testers must keep their equipment in good condition, calibrate it yearly, and perform any necessary repairs. In addition, they must submit test reports to HCA-EH and their water supplier within 10 days of the initial test, regardless of the results.
In addition to having the right equipment, a backflow tester needs to have excellent customer service skills and be detail-oriented. It’s also important for them to be physically fit as they’ll often be walking, standing, or working in tight spaces.
A career in plumbing requires extensive on-the-job training and experience. However, there are several ways to get started in this industry, including going through a trade school or apprenticeship program. While these programs aren’t as long as a bachelor’s degree, they can still provide a solid foundation for a successful career.
Whether you need to test your backflow prevention device or want to hire a licensed backflow tester, Kiddco Plumbing is here for you. We’ll handle everything from shutting off your water to submitting your report to the city, so give us a call today!