The answer to 'backflow preventer replacement frequency' is that backflow preventers should be inspected and tested annually, and replaced every 5-10 years on average. Backflow preventers are an important safety device that prevent contaminated water from flowing back into the clean water supply. Over time, the internal components can wear out and become less effective, so regular maintenance and replacement is recommended to ensure proper function.
The exact replacement frequency can vary depending on the specific device, water quality, and usage. Some backflow preventers may last 10 years or more with proper care, while others may need replacement sooner. It's best to have a licensed plumber inspect the device annually and recommend the appropriate replacement timeline.