NFPA 25 requires professional fire sprinkler head replacement every 10 years. However, industry best practices suggest performing quarterly inspections as well by a Certified Licensed Professional. 

15.2.1. Inspection

When replacing the head on a dry sprinkler system, a professional has to make sure the system doesn’t trip and flood the pipe plus re-pressurize the system. A precaution system uses valves controlled by other sensors to prevent the accidental discharge of water. Bear in mind that the old fire sprinkler heads get thrown out. They can’t be repaired and reused, even if it seems like a problem can be fixed. Section of NFPA 25 makes this explicit: “When a sprinkler has been removed for any reason, it shall not be reinstalled.”