Source for 12 Volt Smoke Detectors?

[WoodieSC]

When we designed and had our house built, I also installed a security system that included 12 volt smoke detectors on each level wired into the central system panel.

The detectors are on a 4 wire circuit, linked together and then to the panel.

They need to be replaced due to age, but I'm only finding 120V detectors and every source I've found say that it's unsafe (and illegal?) to tie the 120V detectors into a 12V panel through a relay.

Does anyone know of a reputable source - other than the Chinese crap on eBay - for 12 volt ionization and/or photoelectric smoke alarms?

If I can't find any, I guess I can rewire the detector circuit to tie the primary alarms together, but they won't be linked to the central security system.

Suggestions, recommendations?

Thanks.

[Joe Krasko]

You will need to take the wiring that originates from the 12V source to a 120V source, then change out the smoke detectors. There is a transformer or battery source that powers yours system now. If the source is a transformer it's simple as removing the transformer and wiring the new detectors.

[waterbreaker]

Is your security panel still active. I can tell you where to find detectors to replace yours but they must work in conjunction with your panel as they don't have a siren built in. You can also just buy battery operated smokes that interconnect so if one goes off they all go off.

[Goin Coastal]

RV supply place?

[WoodieSC]

You will need to take the wiring that originates from the 12V source to a 120V source, then change out the smoke detectors. There is a transformer or battery source that powers yours system now. If the source is a transformer it's simple as removing the transformer and wiring the new detectors.

Yes, the main panel is powered by a 12V plug-in adapter and the security accessories and the smoke detector chain are all connected to that.

I can re-wire at least the three main detectors on the first and second floor in a chain, but not sure if I can run the wire to the basement one. I'd have to pull the house wiring schematic to see if it's possible. I'd also have to check to see what I'd need to do to link the detector chain to the external bullhorn.

I do also have several battery operated detectors on each floor so that I've got both the main 'monitored' alarms in the halls and main rooms along with individual ones in bedrooms, etc, etc.

I just didn't want to separate the smoke detector circuit from the main panel if I didn't have to.

Is your security panel still active. I can tell you where to find detectors to replace yours but they must work in conjunction with your panel as they don't have a siren built in. You can also just buy battery operated smokes that interconnect so if one goes off they all go off.

Yes, the panel is active and has both a local test alarm and an external bull horn siren. However, with one detector in the basement, it would have to have a local alarm or it wouldn't do much good to have the alarm in the main panel sound off and not tell you which alarm is going off. Precious time could be wasted trying to track it down. But I suppose small sirens could easily be wired in to each detector if needed.

I don't recall seeing the battery operated ones that can be interconnected. Can I 'assume' that I could use the existing 22/4 wiring for the connecting circuit? I'd think that would do the trick.

RV supply place?

Ahh... good suggestion. I've seen RV CO2 detectors, but hadn't poked deep enough to check on the smoke detectors.

Does anyone know if all the laws have been changed such that the 120V alarms are now required and the 12V systems aren't allowed? I haven't gotten into the SC or National Electrical code to try to understand it.

Thanks.

[WoodieSC]

This dang smoke detector business has gotten as full of distracting choices as the phone market has. It's crazy.

Unless my total cost would be a lot less going direct wired, I'm thinking of going with the first detector in the basement being wired to it's own 120V/20 amp circuit breaker in the main panel... and then installing another six to nine wireless ones throughout the house that will supposedly all 'talk' to each other without having to screw around with an Iris router or whatever it is. At least I think I've got that figured out.

The detectors will be photoelectric with a CO2 detector (or combo one) on each level.

I need to read up on it some more to make sure I've got this understood.

Note - I am aware that the NFPA recommends that both types of detectors (Ionization and photoelectric) be installed, or that combo units be used. However, there appears to be some evidence that indicates that the photo units detect a fire much faster than the ion ones do.

Here's a study from Texas A&M from 1995 the surely should have had an impact on the market, but apparently didn't.

http://www.thewfsf.org/texasaandm

Read the summaries on page 17.




Any other solid suggestions would be welcome.

Thanks.

[GreenHeadRocker]

Speaking of smoke detectors.... Mine sounded off the other night about midnight. Scared the hell out of me. Only lasted about 10 seconds. Ended up being the upstairs detector. Pulled the battery the next day and put it back in. Tested and returned to service. Keep in mind these are only about 3 months old too.

[WoodieSC]

Speaking of smoke detectors.... Mine sounded off the other night about midnight. Scared the hell out of me. Only lasted about 10 seconds. Ended up being the upstairs detector. Pulled the battery the next day and put it back in. Tested and returned to service. Keep in mind these are only about 3 months old too.

One my my upstairs battery operated ones started blaring about 8pm last night. I took the battery out to silence it, figuring the battery was low. But a low battery alarm tends to 'chirp' instead of blasting full sound, and then the battery tested at a full 9 volts. I checked all around the upstairs and in the attic and couldn't locate any source of smoke, etc, so I'm guessing the alarm is bad.

I just find it a little ironic that a few weeks ago my wired alarm right in the upstairs hall goes off, and then this battery alarm on the other side of the door goes off last night. It's spooky.

I'm hoping to decide on which ones to put in this weekend so that I'm not leaving too many alarms disconnected any longer than I need to. I've got backups everywhere for now, but it's an uncomfortable feeling.

[GreenHeadRocker]

Yea these in the new house are wired with battery backup. Still don't know exactly why they went off.