Sprinkler-Flow Switch Zoned to the Wrong NAC
A 12-story office tower has a newly installed addressable fire alarm system. The installer placed the sprinkler waterflow switch for the Level 6 riser on the same notification appliance circuit as the Level 6 manual pull stations, but the flow switch was programmed as a supervisory (trouble-only) point rather than an alarm point. During acceptance testing, water flowing from a Level 6 head produced a supervisory signal at the FACP and a local trouble buzzer, but no horns or strobes activated anywhere in the building. The plans show the flow switch on a dedicated monitor module addressed to a general alarm group. The installing contractor argues the device is 'supervised' and therefore compliant. The AHJ has not yet signed off. The building is fully occupied and the owner is pushing for immediate acceptance.
1. Is the contractor's argument that a 'supervised' supervisory signal satisfies code? Explain what the waterflow switch must do and why.
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No. 'Supervised' describes circuit integrity monitoring, not the required alarm response. A sprinkler waterflow switch is an alarm-initiating device; when it operates, the system must enter the alarm mode and activate notification appliances. Programming it as supervisory-only means the system annunciates a trouble condition and stays silent, which defeats the purpose of the device. The correct configuration is an alarm point assigned to the appropriate alarm group (general alarm or the affected zone's notification), consistent with the approved plans. The contractor's use of the word 'supervised' conflates two unrelated concepts and does not cure the misconfiguration. The AHJ should reject the point as programmed.
2. The contractor proposes to 'just reprogram the module to alarm' without touching wiring. What else must be verified before the AHJ accepts the correction?
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Reprogramming alone is not sufficient. Verify: (1) the module's address and zone assignment match the approved plans and the correct notification group; (2) the device is listed for the application and its wiring is Class B or Class A as designed; (3) the waterflow switch actually operates at the intended flow and the module reports alarm, not supervisory, at the FACP; (4) notification appliances on the assigned group audibly and visibly activate throughout the protected area; (5) the alarm is annunciated at the FACP with correct location text; (6) retest and document per the acceptance test plan, and update as-built programming records. A witnessed retest of the flow switch and the affected NACs should be required before sign-off.