over 12 smoke detectors,

Status
Not open for further replies.

wireman3736

Senior Member
Location
Vermont/Mass.
I have never done a residential house with more then 12 smoke alarms. Does anyone know of a way out of this with out installing a fire alarm system?

Thanks Stan
 

mdshunk

Senior Member
Location
Right here.
You can put one of those relay thingamajigs in the 11th smoke detector, and start all over again with 12 more on another circuit. Note that the interconnect voltage for some BRK smoke detectors was changed from 120 volts to 9 volts some years ago, so that might not work for certain BRK's. There's probably some code a smart person will dig up that would cause you to use a "system" for more than 12. Seems like I tried to get my head around the fire alarm code some time back, and it's among the most confusing documents I've ever tried to read.
 
Last edited:
This has come up numerous times in our area, as there are many homes of over 10,000 sqft being built. The answer so far has always been to install a fire alarm system...maybe some manufacturer has come up with a fix that we are not aware of. The Kidde system with 18 devices is still limited to 12 smokes.

In NYS, the smokes all have to sound at the same time, from the basement to the attic, there are no exceptions.
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Tom, what building code(s) govern your area?

Roger
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
Our State Electrical Act does not include enforcement of smoke detector installation at all so the Electrical inspectors do not even look for them other than inspecting the wiring itself. State law has a minimum for placement but no enforcement and no inspection for them in single family dwellings. Area cities do have more stringent regulations but in rural areas you are on your own.
 

badabing

Member
Pierre C Belarge said:
The Kidde system with 18 devices is still limited to 12 smokes.


The kiddie system is not limited to 12, it has support for up to 24 devices and is limited to 18 initating devices as i stated earlier.

From the Kiddie instruction pages (that i linked):

UTHA / UTGT Compliant
Smoke Alarm
• Model 1296
A maximum of 24 Kidde devices can
be interconnected in a multiple station arrangement. The interconnect system
must not exceed the NFPA (National Fire Protection Association) limit of 18
initiating devices (Smoke, heat, CO, etc) interconnected, it is still possible to
interconnect 6 strobe lights and or relay modules.
 

wireman3736

Senior Member
Location
Vermont/Mass.
nfpa 72 states no more then 12 smokes, if the circuit is supervised then up to 42 smokes.:mad: I'm going to give the prints to the owner and let him get with his arc. to settle it with the local fire inspector. I quoted the job but didn't pick up on 14 smokes being too many, I never realized there was UL and NFPA requirements limiting household smokes that are unsupervised. There was nothing on the prints or specs that listed a fire alarm system. Hopefully there won't be a battle over this.:rolleyes:
 
From the Kidde website, the manual (I think this was page 6)...

"• A maximum of 24 devices may be hardwire interconnected in a multiple station arrangement.
The interconnect system should not exceed the NFPA interconnect limit of 12
smoke alarms and/or 18 alarms total (smoke, heat, carbon monoxide, etc.). With 18
alarms interconnected, it is still possible to interconnect up to a total of 6 remote signaling
devices and/or relay modules."

The rest of the manual is here:

http://www.kidde.com/utcfs/ws-384/Assets/Wireless AC Manual.pdf
 

bob cape may

Member
Location
New Jersey
if you put in a remote signaling device to get more smokes than it has to be supervised syste. as per NFPA 72 11.8.2.2 also once these limits have been exceeded a fire alarm system should be installed
 

badabing

Member
I'm sorry, maybe i don't fully understand this. In the NFPA it states that Smoke "alarms" shall not be interconnected with more then 18 initiating devices of which no more then 12 can be smoke "alarms", it says nothing for smoke "detectors". Are these or are they not different things? They both have different definitions in the book... Maybe it could be clearified for me?

11.8.2.1 says Smoke detectors shall be connected to central controls for power, signal processing, and activation of notification appliances.

11.8.2.2 says the interconnection of Smoke or heat alarms..
 

kkwong

Senior Member
My interpretation of the two definitions is:

Smoke Detector: Local alarm only. For use to alert tennants/occupants in a given area. Does NOT report to FACP. NOT interconnected with bldg's fire alarm system.

Smoke Alarm: Tied in to bldg's fire alarm system. May or may not initiate sprinklers, usually initiates the first side of a preaction sprinkler system.

Hope that helps. :)
 
Status
Not open for further replies.
Top