The answer to 'backflow preventer constantly running' is that a backflow preventer that is constantly running is usually a sign of a problem. A backflow preventer is a safety device installed in plumbing systems to prevent contaminated water from flowing back into the clean water supply. If it is constantly running, it could indicate a blockage, a broken component, or a problem with the water pressure.
Some common causes include a clogged or stuck check valve, a problem with the diaphragm, or an issue with the water pressure. Symptoms may include constant water flow, water leaks, or reduced water pressure. Solutions can include cleaning or replacing the backflow preventer components, adjusting the water pressure, or calling a professional plumber for more complex repairs.