How often must a dry system be inspected?
NFPA #13A and 25 call for partial flow tests annually and full flow tests every three years. Since they also caution that some types of dry valves do not function and trip correctly on partial flow tests it is recommended and the normal practice to full flow test dry system annually. Since the liability of full flow tests is so great only qualified persons should trip test dry systems. Except an inspection report filled out completely by a qualified and reputable person or company, I know of no way to identify if a valves has been tripped and tested. The only way to trip a dry valve is to release the air pressure in the system. If this has been inadvertently done the cheapest solution in the long run is to call the contractor who installed or maintains the system to reset and drain the system. This policy may cost several hundred dollars but in the long run will eliminate the more costly freeze up and system break down.
