# Fire alarm troubleshooting



## mikeh32 (Feb 16, 2009)

I will ask a friend who only does fire


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## cuba_pete (Dec 8, 2011)

Run impedance checks on the pull station and circuit wiring runs...megger out the runs


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## LightsOn81 (Jan 6, 2012)

Culd the heat detectors be placed in such a position that the heat from the metal and the sun shining on it be setting it off? Are these random false alarms or is it regular and predictable? It could be that this thing will go off when the conditions are just right..........? I'm not a fire alarm guru but it might explain something


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## mbednarik (Oct 10, 2011)

the last FA system i worked on had a red light on each of the smoke/heat heads that would flash if it was the one signaling. But i think you have to silence the FACP not reset it. I think when you reset everything the head resets too.


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## Nigelforsythe (Jun 26, 2010)

LightsOn81 said:


> Culd the heat detectors be placed in such a position that the heat from the metal and the sun shining on it be setting it off? Are these random false alarms or is it regular and predictable? It could be that this thing will go off when the conditions are just right..........? I'm not a fire alarm guru but it might explain something


It's in a 100 year old basement so there is absolutely no source of heat in any of the units. It's probably a ghost


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## Nigelforsythe (Jun 26, 2010)

mbednarik said:


> the last FA system i worked on had a red light on each of the smoke/heat heads that would flash if it was the one signaling. But i think you have to silence the FACP not reset it. I think when you reset everything the head resets too.


No indicating lights on the devices. Looks like we are going to do a full system test to make sure there aren't any devices tied into this zone in weird spots throughout the building


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## bkenney (Feb 15, 2010)

If its cold and a rate of rise heat detector is near a light bulb, hvac vent, or hot water/ steam pipe that could activate. Usually a rate of rise heat is looking for a temp change of 15 deg in 30 seconds ( or close to that) also being conventional any short in the zone will activate. Is it always the same zone?


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## zwodubber (Feb 24, 2011)

Make sure you set the system to bypass before working on it, learned that the hard way and wont forget again.

Is the wire run in conduit? We had a forklift hit a pipe and nick a wire once, after that anytime something bumped the conduit slightly the exposed wire would hit the pipe and trigger an alarm. Do continuity tests between all the wires and the conduit.

Another incident we got called for were sporadic alarms at a cold food storage facility. The wires from the main unit went straight up conduit and had been filled with some sort of silicone to prevent condensation from coming down into the unit. It broke down and water started dripping on the boards triggering alarms.

Another simple thing is to check for end of line resistors at the pull stations and make sure they are in place firmly.

If I think of more I'll post them later, hope this helps.


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## sarness (Sep 14, 2010)

Something else to try if you can is to split it up into more zones, might help narrow it down.


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## Nigelforsythe (Jun 26, 2010)

It's all surface wiring with no signs of visible damage to any of the wiring. Today we did a full fire alarm system test checking every device in the building and everything checked out okay. I swapped two zones in the panel hoping that it would prove that something was internally wrong in the fire alarm panel but I just heard from the boss that the alarm signal has moved to the new zone so it has to be something to do with the wiring... 

No heat sources near any of the heat detectors and whenever it does go into alarm we can immediately reset it and the fault is cleared. Makes me think there's a very temporary short cct somewhere in the loop. Possibly due to a damaged wire and vibration. 

It would help us out if whatever is causing the alarm would stay in it's shorted state for longer than 10 seconds and we could begin to narrow it down


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## Edrick (Jun 6, 2010)

How many devices are on that zone? Have you visually inspected all the connection points on that zone? Is it frequent enough you could remove a device at a time and see if it continues?


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## electricalperson (Jan 11, 2008)

moisture getting into the boxes?


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## NacBooster29 (Oct 25, 2010)

On a surface mounted cable system like yours I would be looking at a staple done up too tight. When the bldg moves, which they do. It maybe causing your false alarm. I'm guessing its.not the onetime use heats. Best bet is breaking the loop into halves if it is run class a and you have a spare zone at the panel narrow your search by 50%. I'm.guessing it was a conventional.system by the op.


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## leland (Dec 28, 2007)

Nigelforsythe said:


> The zone that is causing the alarm signal is a mini storage with around 40 heat detectors, one pull station and no smoke detectors.
> 
> 
> Thanks for reading my novel. Any help is appreciated!


And a great Novel it is. Too bad we had to read all that to get to this.

How old is the system?

#1- is it all in conduit? Over head or under ground?
#2- Have you opened up the pull station? Probably located out side and subject to moisture. Over time these contact closure devices do fail.
#3- Change all the heat detectors. (What type are they?)

Cheap enough. $5- $10 each- Depending on access to the units- 10 -15 min. each- (Depending on the mechanic doing it) (doesn't that suck? Gotta bid a job based on who you assign to it.(AAARRRGG)) 
$20 mic materials- stake on's etc.

I have in the last 4 months, had 3 fail, Chemtronics - Edwards- what ever they are labeled. Perfectly fine on the surface- failed on the guts.


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## farlsincharge (Dec 31, 2010)

The last time I had a trouble like this it ended up being the pull station. I would say, for all the time it takes, remove it from the circuit and see what happens


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## macmikeman (Jan 23, 2007)

Replace the eol's too.


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## JohnR (Apr 12, 2010)

Check each smoke head for small spiders then spray an insect deterrent around each head to keep them from re/entering. Could check for rodent chewing as well.


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## leland (Dec 28, 2007)

macmikeman said:


> Replace the eol's too.



Mac- That is a great point !!!! :thumbsup::thumbsup::thumbsup:

The ones that come in the panels (talking conventional) Are typically 1/4 watt.
The field ones should be no less than 3/4 to 1 watt, this also depends on the devices # of and type.
Add the resistance of the conductors- 1/4 is gone real fast and then they fail.


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## TattooMan (Feb 10, 2012)

Nigelforsythe said:


> Hey everyone, just wondering if any of you have some helpful tips or hints for troubleshooting a fire alarm system. We have a customer who's dealing with their system going into false alarms randomly (sometimes once a month, sometimes twice a day) and would love to have the system fixed before they start getting charged by the local fire department for callouts.
> 
> It is a non addressable edwards est1 2400 series panel. When it does radomly choose to go into alarm we are able to reset and clear the panel without it going back into alarm.
> 
> ...


Kind of curious of this was ever resolved. If everything has been checked like it sounds like you have done and all of the devices are in working order then it sounds like a re-pull is in order. Sell the customer on some conduit as well while you are at it.


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## don_resqcapt19 (Jul 18, 2010)

Unless the EOL shorts, which would not be very common, a failed EOL will only give you a trouble, not a fire alarm.


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## TattooMan (Feb 10, 2012)

don_resqcapt19 said:


> Unless the EOL shorts, which would not be very common, a failed EOL will only give you a trouble, not a fire alarm.


Funny story. I was demoing an old Siemens system yesterday and came across 3 shorted eols. Go figure...


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## leland (Dec 28, 2007)

TattooMan said:


> Funny story. I was demoing an old Siemens system yesterday and came across 3 shorted eols. Go figure...



Pyrotronics- yep- those capacitors do fail after time.


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