Waterflow Timing, a Bypassed Tamper, and a Silent Exterior Appliance
You are performing the annual inspection and test of a wet-pipe sprinkler monitoring system in a 40,000 sq ft warehouse. The fire alarm control unit is a 24-volt addressable panel with a waterflow switch and a tamper switch on the main OS&Y valve. During the flow test, the waterflow switch activates a visible alarm at the panel 95 seconds after you open the inspector's test valve; the panel is programmed with a 90-second waterflow retard. The tamper switch circuit is bypassed at the panel with a jumper wire, and the panel shows 'SUPERVISORY BYPASS.' The warehouse manager says the tamper switch 'keeps going into trouble' and the maintenance technician jumpered it 'temporarily' three weeks ago. You also notice that the waterflow alarm did not activate the exterior horn/strobe, although the panel display shows the alarm.
1. Evaluate the 95-second waterflow alarm. Pass or fail? What is the basis?
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Fail. The panel is programmed with a 90-second retard, and the alarm annunciated at 95 seconds. A waterflow switch must initiate an alarm within the allowed time after flow begins; exceeding it indicates a problem with the retard setting, the paddle adjustment, the switch, or the programming. Retest after correcting the cause. Do not average or round down. Record the measured time and the device. A marginal pass is not acceptable because the next test may drift further.
2. What must be done about the bypassed tamper switch?
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A bypassed tamper switch removes supervision of the main control valve. That is an impairment, not a temporary convenience. The jumper must be removed, the circuit restored, and the tamper switch tested for open and close positions and supervisory signal. If the switch or wiring is defective, repair or replace it. Notify the owner and the monitoring company of the impairment and document when it began if known. Do not leave the system with the bypass in place. If restoration cannot be completed, follow the impairment procedures and notify the authority having jurisdiction as required.
3. The exterior horn/strobe did not operate during the waterflow test. What now?
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Treat it as a failed notification appliance. Verify whether it is on the same circuit, whether it was bypassed or disabled, and whether the panel programming maps the waterflow zone to the exterior appliance. Check voltage at the device and the circuit wiring. The system cannot be considered fully functional until the appliance operates. Record the deficiency, retest after repair, and note whether the failure could affect occupants or fire department response.