Many homes and commercial building have a backflow preventer valve. Properties that have large boilers, fire suppression systems, or irrigation systems, will most likely have a backflow preventer valve installed.
These devices are installed in areas where municipal clean water supplies cross-connect with contaminated, waste water sources. The preventer valves keep these two water sources from mixing and contaminating clean water supplies through a backflow.
Backflow is caused by pressure differences, that result in water moving in the wrong direction and contaminating a potable water supply.
Backflow valves are crucial for preventing hazardous contaminants, such as bacteria, chemicals and sediment, from making their way into everyone’s drinking water. If you have a backflow valve installed, you’re required to have professional backflow testing conducted once a year.
Common Problems with Backflow Prevention
Some of the most common problems that could cause your backflow preventer to fail include:
Faulty First Check Valve
The first check valve in a reduced pressure backup preventer is designed to open at certain water pressures. This allows the water to become pressurized in the space between the first and second check valves. Once the correct pressure is reached, the valve opens, however, if it’s faulty, it might open at lower pressures, impairing its performance.
Faulty Second Check Valve
Backflow testing for the second check valve looks for signs of backpressure. If it fails, water can leak past it, back into the area between check valves.
Relief Valve Opening Point is Too High
When water enters the relief valve, pressure builds up to compress a spring, which moves the relief valve disc to block the seal. Backflow preventers are designed with different minimum thresholds, therefore the threshold can become too high, if the relief valve disc does not embed itself correctly.
Relief Valve Opening Point is Too Low
The relief valve opening point can also become too low, because something is restricting movement into the relief valve stem mechanism. This can be caused by corrosion.
Signs that You Need a Backflow Test
- The biggest sign is the amount of time that has past since the last inspection/ test of the backflow valves. Due to potential health risks, your backflow system needs to be tested annually. If you have a backflow prevention system that has not been tested in the past year, there could be issues with it that you are not unaware of.
- If your area has recently experienced severe weather, this can result in wear and tear and cause certain parts of the assembly to break down.
- Visible signs you need backflow assembly repairs include leaks or discharge from the assembly. This can be caused by dirt and debris, fluctuation or negative pressure in the system, or thermal expansion.
- Dripping water is a sign that there is a failure in the device and it will need to be repaired as soon as possible.
- The most dangerous and urgent sign is if your clean water appears cloudy or discolored. If anything about the water from your taps looks strange, you should avoid its consumption and call in professionals to test the system and resolve any issues.
The reality is backflow systems can break down and water can become contaminated and undrinkable. Drinking water from a broken backflow assembly can lead to serious illness and even death. Make sure to test your backflow assembly annually and call professionals if you suspect an issue.