Sprinkler leaks in general seem as soggy spots, low strain, or effervescent at heads
https://threadvistax.com/s/xUqz8P5KyWKT47Q4UxhPI
Sprinkler leaks many times seem as soggy spots, low strain, or bubbling at heads. Inspect risers, lateral traces, and valves, then fix cracked fittings to restoration system overall performance.