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Ask the Technician


Why reverse polarity for fire alarm horns? -- A fire horn is turned like a light; it turns on when power is applied and turns off when power is removed. But then again, to constantly check continuity of the wires (supervise the wires), the Fire Alarm Control Panel (FACP) always has power applied to the circuit. Read More

Can I Mix High and Low Voltage Wiring? -- Can phone lines, fire alarm cables, and 120-240 cables be put together in an outdoor back box? Read More

Can a Button be Installed to Release a Door Holder? -- The workers have to pop the door off the magnet when church starts. Some of the workers are older and have difficulty closing the door. Read More

What Causes an Open NAC? -- I am going to a job site where on the service call ticket states that a NAC is reading open circuit. What can cause an open circuit on the NAC line? Read More

Can the fire department make the owner bring the whole fire alarm system up to code? -- We failed the inspection with city due to lack of signage at pull stations in an existing apartment building. The signs are supposed to say LOCAL ALARM ONLY - IN CASE OF FIRE CALL 911 Read More

I'm Having Trouble With a Door Release -- While trying to trouble shoot why the door release for the front door is not working, one of the conductors grounded out against the fire alarm panel chases. This caused the door release to activate. Any thoughts? Read More

Are All Smoke Detectors Polarity Sensitive? -- I have a question... Is it important for smoke detectors to be polarity correct? Are all smoke detectors polarity sensitive? Read More

Can You Tell Me how the Red Box on the Wall Operates? -- I moved into a 1-bedroom apartment recently that has 3 smoke detectors (the flat, round kind mounted on the ceiling), but also mounted on one wall is a red strobe alarm... Read More

Do I Have to Go Off Line? -- Do I have to go offline to replace the batteries in the duct detector panel? Also, will I have to reset any equipment or systems? Read More

Can I Relocate a Strobe Without Reprogramming? -- Do the technicians have to reprogram the fire alarm system after relocating devices just a few inches from their original position? Read More

Can We Use Waterflow Switches for Liquid Suppression Systems? -- Can we use the Flow Switches and Pressure Switches that are used with water lines, for fire suppression system, if fire suppression system uses NOVEC 1230 liquid? Read More

How Can We Fix Intermittent Beeping Troubles? -- We have a fire alarm system installed ~ 2000, it started beeping trouble, runs through all the points as troubles, then restores to normal. Fire alarm technicians cannot figure it out. Read More

Is There Any Reference to Font Size for Labels? -- Is there any clear info on the marking as to Font size? As for 10.6.5.2.3 is there a better description for a red marking, one that is uniform with code? Read More

How do I troubleshoot a ground fault? -- Troubleshooting a ground fault is like troubleshooting anything else. The first thing to do is stop and think. Ask yourself, what are you looking at? Read More