Every once in a while I see sprinkler heads that their liquid bulb is spray painted. As the temperature rises in the event of a fire, the bulb breaks, and letting a valve above it drop down and release water through that head. If the sprinkler head is painted over, the paint will actually protect the bulb, preventing it from breaking at the right temperature and prevent water from being released. Spray painted liquid bulbs should be replaced, cleaning them is not a safe option. If you have one or more painted sprinkler heads in your property, you should consult with a certified fire sprinkler contractor for replacement.
