The answer to 'backflow preventer not working' is that a malfunctioning backflow preventer can have several common causes, including debris buildup, wear and tear, or improper installation. Symptoms may include water flowing back into the home, low water pressure, or contaminated water. To troubleshoot and fix a backflow preventer issue, you can try cleaning or replacing the device, but in many cases it's best to call a professional plumber.
Backflow preventers are an important safety device that keep contaminated water from flowing back into your home's clean water supply. If the backflow preventer is not working properly, it can pose a serious health risk. Attempting to repair or replace a backflow preventer yourself may require specialized tools and knowledge, so it's usually best to call in a licensed plumber for this task.