Final answer:
Strainers equipped with a differential pressure (DP) gauge should be inspected daily and cleaned when the DP reading in psi reaches at least 10 psi.
Step-by-step explanation:
Strainers equipped with a differential pressure (DP) gauge should be inspected daily and cleaned when the DP reading in pounds per square inch (psi) reaches at least 10 psi. This is because as the pressure difference across the strainer increases, it indicates that the strainer is becoming clogged with debris.
Cleaning the strainer at this point helps maintain optimal flow and prevent damage to the system.