With the sprayer head removed, prepare a small bowl with enough white vinegar to fully submerge it. Place the sprayer head in the bowl and let it soak for at least one hour (or overnight for heavy buildup). The acetic acid in the vinegar will dissolve the mineral deposits. While it soaks, use a small brush, like an old toothbrush, to gently scrub the nozzle holes and the inlet screen to dislodge any remaining debris. After soaking, rinse the sprayer head thoroughly with warm water, both inside and out. To test if the clog was in the head, place the end of the sprayer hose in a bucket and slowly turn on the water valves. If you have strong pressure from the hose, the clog was in the sprayer head.