Alarm Check Valves and DCVA

[simply4you]

Help me here….I designed a wet sprinkler system having an alarm check valve in the system riser with multiple sprinkler zones on each floor. Each sprinkler zone is provided with supervised shut-off valve and flow switch. Our Building Code requires now a double check valve assembly on all incoming fire mains. The Contractor doesn’t want to provide an alarm check valve downstream of the DCVA (which is a Wilkins Model 350) as he find it to be redundant. Will this installation without alarm check valve in the system riser still meet the requirements of NFPA 13?

 

[SprinklerDesigner2]

Yes, it will.

 

[cdafd]

can you say dick shaney: shotgun

not sure if 8.15.1.1.3.2 nfpa 13 2002 answers the question

 

[simply4you]

With the alarm check valve in the system riser, the sprinkler side of the system is pressurized above peak incoming pressure to prevent false alarms. With the DCVA how do we do it? A time delay in the flow switch would be an acceptable solution? Is the time delay permitted by NFPA?

 

[SprinklerDesigner2]

The DCVA behaves the same way as an alarm check valve.

Time delay on flow switch is necessary and acceptable. I would set it for 90 seconds and go from there.