Smoke Detectors in Multifamily building

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I live in a 10 unit condo building and I have a problem with my smoke detector. No one on our condo board seems to know anything about them.

The history is that we had a fire originating in a ground floor unit 10 or 12 years ago. Seattle FD station is 5 blocks away, and they got it put out with relatively modest damage and no injuries. The fire department along with our insurance carrier mandated that we install Kidde i5000 ionization smoke detectors that use AC power and have a 9 volt battery backup and are linked with all other detectors in the building.

https://www.amazon.com/s/ref=nb_sb_...=aps&field-keywords=Kidde+5000+smoke+detector.

Recently my detector started just going off when there is no smoke or heat anywhere in my unit or elsewhere in the building or even outside. After waking up, looking all over, feeling some doors etc, I proved to my satisfaction that there was no fire. It was the alarm sounding, not that chirping that tries to tell us to change the battery. So I ordered a new device. I hope this solves the random going off.

But I would like to understand how these linked detectors are supposed to function. The wiring harness includes 3 wires- power, grounded neutral, and a yellow wire that is supposed to link with other units in the building. It must be some sort of parallel circuit, because there is only one wire other than the power and neutral. I imagine that the power is stepped down at a transformer that I haven't found. but not sure. Anyway we are required to maintain these linked detectors, and since no one here seems to understand how these devices are supposed to work, I thought I might be able to find help here. One thing I know- when I disconnected my detector, and left it disconnected for several weeks, no one even knew about it. I also have a 10 year self contained detector with a sealed lithium battery, that I use as a personal backup. After 10 years one just replaces this whole thing.

I figure this would warn me of anything that changed the air in my unit, but I would like to understand the proper use of the linked Kidde AC units which when I receive the new one I will be hooking up.

Can anybody explain the principles of these ac powered, linked detectors?

Thanks much.

Ha
 
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If the SA are interconnected when yours went off did it set off all of the others?

If so, how do you know yours was not set off by some other SA activating?
 
they must be replaced every 7 years

if its anything like the ones i was forced to put into my brand new home , they have a life span, automatically they start beeping after a certain amount of time. they need to be replaced, new batteries wont shut them up. i have 10 foot ceilings i cant make out the model number, its a different look one but its kiddie. all that being said i had to remove one to replace the battery, none of the other alarms went off. when i had a smoke condition once, holly cow, all 4 floors went off, you could have awoke the dead. So if i lived in a multifamily complex, my take away is all the others could yank their smoke detector down and i would be unprotected.
 
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Just a guess that most have been disconnected between the condo units.

Do you have some kind of alarm panel in the lobby or underground garage if applicable?

Maybe a door to a utility room with a small placard " FACP INSIDE " ( fire alarm control panel).

I suggest going to your local fire station and asking . The departments are usually helpful.

PS Most multi family buildings in metropolitan areas are inspected yearly by the fire department. If this is an issue, the FD needs to know about it.
 
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I'm guessing that the 3rd wire has no power normally, and when a detector goes off, it gets connected to the power by the screaming alarm.
All the other connected alarms go off when power is supplied to this normally neutral wire.

Of course I'm just thinking this out loud, and could easily be wrong. If you had a voltage detector, you could see if this 3rd wire really is dead, and then supply 9 volt + to it, and see if your neighbors all come running out the doors ;)

(Just_Steve posted before I finished typing, so my thinking might be too simple ? )
 
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A timely post for me. I have no answers for you, just my experience. Early one morning this week my kidde alarm, one of four all hard wired to my electrical box went off. There was no fire or smoke anywhere. What a terrible experience it was for my elderly pets especially. i was forced to install them when I had major electrical repairs after tree damage last June. Only way to get the house up to county code, which was the only way to get the power co to restore power. I tripped the breaker on the smoke alarms and after I guess the back up battery gave out, they were finally quiet. Will depend on the one battery powered only smoke alarm I already had before the June event from now on. What a waste of money.
 
I'm guessing that the 3rd wire has no power normally, and when a detector goes off, it gets connected to the power by the screaming alarm.
All the other connected alarms go off when power is supplied to this normally neutral wire.

Of course I'm just thinking this out loud, and could easily be wrong. If you had a voltage detector, you could see if this 3rd wire really is dead, and then supply 9 volt + to it, and see if your neighbors all come running out the doors ;)

(Just_Steve posted before I finished typing, so my thinking might be too simple ? )

You are correct - the diagram shows that same thing (I'm not sure what signal is used on that wire though, could be 9V, or 120V, or a switch to ground - doesn't matter, concept is the same).

I'll agree with others, check with HOA and FD to understand how many are connected together (one floor, the whole building?), and if everything is still compliant. And I think it is a good idea to keep a separate battery unit - that way you are protected in case some kind of fault happened that affected the whole system (not sure that's possible, but a separate alarm is cheap insurance).

I also look for ones with a MUTE button - great for nuisance alarms while cooking. Push the button and it mutes for 5 minutes or so. Avoids the temptation to disconnect the unit. I feel this should be required by code. They also make units that can be muted with a TV remote, in case they are mounted out of reach.

-ERD50
 
Kidde is still in business. They are going to have a customer service department and local dealers. This is really nothing to mess around with or to consult the ever-reliable internet about. (My favorite internet cartoon: https://en.wikipedia.org/wiki/On_th...ows_you're_a_dog#/media/File:Internet_dog.jpg )

It's fun to be Sherlock Holmes but I would not be relying on my acumen when my smoke detector is interconnected to others that I have no control over. And I have an MSEE degree.

I would say: Get thee to an expert and have the entire system inspected!
 
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We live in a 27 units townhome development with attached clusters of 3 and 5 units homes. The units are two to three stories and between 2500 to 4000 square feet. All units have their own independent interconnected AC powered CO/Smoke detectors with battery backup and ONE detector that is a connected to a panel at the FD. This detector is our insurance against any owners who disable their detectors. We also have a overhead sprinklers as it is code in our state for any new construction of attached units of 3 or more.

Our unit has 3 smoke only detectors in the bedrooms and 5 CO/smoke detectors in the hallways/basement etc.. A few years ago after few false alarms attributed to one defective CO/smoke detector I replaced all detectors and never had any problems. The new detectors have a 10 year life vs 5 for the old ones.

BTW I only test the detectors when DW is not home as the noise from the 8 detectors is deafening.
 
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We live in a 27 units townhome development with attached clusters of 3 and 5 units homes. The units are two to three stories and between 2500 to 4000 square feet. All units have their own independent interconnected AC powered CO/Smoke detectors with battery backup and ONE detector that is a connected to a panel at the FD. This detector is our insurance against any owners who disable their detectors. We also have a overhead sprinklers as it is code in our state for any new construction of attached units of 3 or more.

Our unit has 3 smoke only detectors in the bedrooms and 5 CO/smoke detectors in the hallways/basement etc.. A few years ago after few false alarms attributed to one defective CO/smoke detector I replaced all detectors and never had any problems. The new detectors have a 10 year life vs 5 for the old ones.

BTW I only test the detectors when DW is not home as the noise from the 8 detectors is deafening.

My contractor pulled a building permit for my 3 story plus 1 basement new house, in July 2010. Due to rampant corruption , you get a different building inspector for every visit. On a bout the 4th visit, he said "you need sprinklers", new law as of January 1st. My architect argued he pulled the permit and had approved plans before the 500 new codes were passed( i dont know how many, but every year its always a few i am told). The review panel at the city agreed with my guy and the Hardwired smoke /fire/cos detectors with battery back up were enough. I asked him "so how much were we talking if i needed sprinklers?", his response 22 Large Big Guy!"(22 thousand). Nice right?already spent 800K on it.
 
Plan

Right now I am relying on my unconnected battery powered unit. When the replacement Kidde i5000 arrives I will install it as before. If it starts giving an alarm on installation I'll approach the board and also walk over to the FD.

Thanks again for all your help.

Ha
 
Given that these were installed after construction, I'd be concerned that they are not truly interconnected. Assuming they were, if your alarm went off, why didn't they all go off? Or, assuming it was another unit causing the alarm, again, why didn't they all go off. Given that you're in a condo, I would go to an association meeting and ask for a periodic test of the entire building. As you have done, I would certainly have a separate unit(s) near my bedroom and possibly my kitchen but I'd feel more comfortable knowing that if another unit had a fire, I'd be notified right away.

As for the wiring, like you said, there's a third wire. That wire is run to all the units. I'm not sure what it's called (series/parallel) but it's just a singe wire from the first unit to the last. I imagine, similar to the ground, that third wire could be run from each unit and joined in a common location.
 
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