Step 2 · Loosen PRV Locknut
Locate the PRV, which is typically a bell-shaped brass valve installed on the main water line shortly after the main shutoff valve and water meter. On the top of the 'bell' is the adjustment mechanism, which consists of a long threaded bolt and a locknut that secures it. To allow for adjustment, you must first loosen this locknut. Place one adjustable wrench on the locknut and another on the adjustment bolt head above it to hold it steady. Turn the wrench on the locknut counter-clockwise about one full turn. This should be enough to allow the adjustment bolt to turn freely.