Replacing old smoke detectors

[BobS0327]

I currently have a Leviton/HAI Omni Pro 2 controller.  There are eight very old System Sensor 2112/24TS smoke detectors connected to the OP2 controller. All of the System Sensor smoke detectors are about 12 years old.  Thus, the age is the reason why I'm replacing them.  IIRC, smoke detectors have to be replaced every ten years.
 
I have eight new DSC FSA-410 Series smoke detectors.  So, my question is, are these new DSC smoke detectors a direct replacement for the old System Sensor smoke detectors?  Or do I have to make any type of wiring adjustments?  Both the old and new smoke detectors are four wire detectors. And if memory serves me correctly, the System Sensors have a EOL power supervision relay installed, part # A77-716 12/24V.  So, should I replace the old relay with a DSC RM-2 End Of Line Pwr Supervison Relay For 4Wire Smoke Detectors.
 
I'm a DIYer not a professional installer.  So, the last time I wired the smoke detectors was 12 years ago. 
 
Any assistance will be greatly appreciated.
 

 

[Del91574]

Personally I was never a fan of the DSC FSA smokes.....hell, they had a huge recall a few years back where they discovered the units wouldn't even alarm in an actual alarm.
 
They're technically a bolt in, however DSC uses a switched negative and SS uses a switched positive. Nature of how the manufacturers and locales they come from have standards.
 
The supervision relay is fine to leave and reuse. You'd need to see how you're resetting the power to the devices at the panel, either switching the negative or positive and adjust accordingly.

 

[BobS0327]

Thanx for the info.  I sorta figured the DSC would be a  direct replacement  for the old smoke detector.  But being a DIYer, I thought I would just double check.
 
If the DSC's do fail for any reason, I have a backup system in place.  The house was built with 120 VAC smoke detectors installed in all the bedrooms and common areas.  Later on, when I installed the OP2,  I  just placed the  controller smoke detectors near the original  120VAC smoke detectors.  So, I now have two smoke detectors in every living area.
 
 

 

[Del91574]

If the existing 120VAC units were of the same or older vintage of the SS units, they're due to be replaced also. Not really a backup if they're EOL also.

 

[ano]

Thanx for the info.  I sorta figured the DSC would be a  direct replacement  for the old smoke detector.  But being a DIYer, I thought I would just double check.
 
If the DSC's do fail for any reason, I have a backup system in place.  The house was built with 120 VAC smoke detectors installed in all the bedrooms and common areas.  Later on, when I installed the OP2,  I  just placed the  controller smoke detectors near the original  120VAC smoke detectors.  So, I now have two smoke detectors in every living area.

As I have mentioned in other posts, panel smoke detectors like the DSC FSA-410 and System Sensor 2112/24TS are both photoelectric detectors, which are less prone to false alarm, so use by panels. This is important to prevent false alarms. In a few areas, smoke detectors on a monitored panel are required to be this type.  The 120V smokes required by the fire codes are typically fast-acting ionization type.  One is certainly not a replacement or backup for the other, they are different types and are designed for different applications.  Also, the 120V smokes are designed to be idiot-proof should you sell your house and the new owner doesn't care about maintaining the panel, they should wake the occupants so they can get out should there be a fire.  Even with "idiot-proof" 120V detectors, it doesn't seem like a day goes by where I don't hear about a death from a house fire were the smoke detectors didn't go off.  Apparently not idiot-proof enough.

 

[BobS0327]

The house was built in 1998.  So, I assume that the 120 VAC smoke detectors  met all applicable fire, building codes in force at that time.  They are very basic 120 VAC smoke detectors which also have a 9 volt battery as backup in case of a power outage.   All the 120 VAC smoke detectors were replaced in 2010.  So, I have a few years left on them.  Also, the batteries are replaced once a year.
 
If the 120 VAC system isn't considered a backup for the other system, I still feel comfortable that the probability of BOTH independent systems failing in a real emergency is very minimal.
 
 

 

[ano]

The house was built in 1998.  So, I assume that the 120 VAC smoke detectors  met all applicable fire, building codes in force at that time.  They are very basic 120 VAC smoke detectors which also have a 9 volt battery as backup in case of a power outage.   All the 120 VAC smoke detectors were replaced in 2010.  So, I have a few years left on them.  Also, the batteries are replaced once a year.
 
If the 120 VAC system isn't considered a backup for the other system, I still feel comfortable that the probability of BOTH independent systems failing in a real emergency is very minimal.
 
 

The house was built in 1998.  So, I assume that the 120 VAC smoke detectors  met all applicable fire, building codes in force at that time.  They are very basic 120 VAC smoke detectors which also have a 9 volt battery as backup in case of a power outage.   All the 120 VAC smoke detectors were replaced in 2010.  So, I have a few years left on them.  Also, the batteries are replaced once a year.
 
If the 120 VAC system isn't considered a backup for the other system, I still feel comfortable that the probability of BOTH independent systems failing in a real emergency is very minimal.

Maintain them like you are and they will work. People shut off the breaker and pull out the battery to silence them and never turn them back on. They are very reliable when correctly maintained. For a very low-cost simple system, they are quite reliable.

 

[pete_c]

If the 120 VAC system isn't considered a backup for the other system, I still feel comfortable that the probability of BOTH independent systems failing in a real emergency is very minimal.
 
In one home replaced all of the contractor installed smokes after 10 years.  The physical replacements were easy but there were many on high ceilings and using a ladder on padded carpeting was not fun.  There are smokes in every room of the house in FL.  This endeavour made me not want to install OPII 2-4 wire smokes.
 
In the midwest the large rooms are covered but the smokes are not as plentiful.  IE: 2nd floor it is just the hallways and no bedrooms where as in FL it is hallways and bedrooms.  It is newer than the house in FL.
 
I do not understand the how's and what of the codes relating to how many 120VAC smokes are installed or supposed to be installed.  Is it just something that varies state to state?

 

[Del91574]

If the 120 VAC system isn't considered a backup for the other system, I still feel comfortable that the probability of BOTH independent systems failing in a real emergency is very minimal.
 
In one home replaced all of the contractor installed smokes after 10 years.  The physical replacements were easy but there were many on high ceilings and using a ladder on padded carpeting was not fun.  There are smokes in every room of the house in FL.  This endeavour made me not want to install OPII 2-4 wire smokes.
 
In the midwest the large rooms are covered but the smokes are not as plentiful.  IE: 2nd floor it is just the hallways and no bedrooms where as in FL it is hallways and bedrooms.  It is newer than the house in FL.
 
I do not understand the how's and what of the codes relating to how many 120VAC smokes are installed or supposed to be installed.  Is it just something that varies state to state?

@ Pete: Code is cut and dry for number and locations of smoke detectors, the only variable is what the AHJ "typically" likes to see.
 
Early 80's to early 90's (memory) was a minimum of 1/floor
 
Minimum for the last 20 years+ has been 1 on each habitable floor, 1 in every bedroom (as legally defined as a room with a door and a closet, no matter how named on the prints) with a detector immediately adjacent to the sleeping areas. Whether or not the detector adjacent is considered the 1 per floor or not is AHJ determination.

The AHJ can mandate where the detector is mounted (big one here is basement, whether or not it's in the basement or top of basement stairs) or if they require one at the top of a 2nd floor stair or if it's put down the hall, if another unit must be added. In the case of a 1st floor master in a 2 story house (IE: colonial) whether or not they want an additional unit installed on the first floor elsewhere in addition to immediately adjacent to the bedroom is AHJ.

The AHJ can't mandate installation of detectors in non-habitable locations or out of the listing operating conditions of the detector itself (IE: attics, crawl spaces or garages). That's been some lively debates with AHJ's that misread the NEC/NFPA and building codes.
 
The only part that is local as far fire alarm/life safety, is whether or not CO (and sometimes smoke) detectors are mandatory on new build, retrofit, remodel or rental. Around here, rentals are required to have smoke detectors (albeit battery ok) however nobody really polices it until there's an incident. CO detectors, although required in new build, are permissible to be battery powered (though many AHJ's mandate they be hardwired)
 
@ Ano's statement with the breakers and batteries, that is somewhat true, which is why many AHJ's want the smoke detector feed wired to a branch circuit and not independent. Not a code requirement, just what they want to see.....same as when some localities mandate that alarm panels can't have plug in transformers with a screw to secure them on anything that has a fire alarm or CO attached. Hardwired breakers only.

 

[pete_c]

Thank you Del.
 
Yup the older home (1999) has 120VAC wired (using romex) smokes in every room except for the bathrooms.  The newer home (2002) only has each floor (X2) and basement covered with 120VAC smokes (using conduit).  Both sets have their own breakers.

 

[ano]

Something to think about for those installing smoke alarms.... and these stats are from 2010 but seem similar to pieces of more recent stats I've seen ...
 
Of the 3000+ people killed in residential fires every year, 40% of the homes didn't have a single smoke alarm.
In 23% of the homes, the home had smoke alarms but they were disabled, mainly due to nuisance alarms from ionization alarms (or dual type alarms) triggering too often.
In 37% of the homes, the smoke alarms were present and working. 
 
Of the 37% that had working smoke alarms, the alarm went off too late, they didn't know they should leave (a large part actually), or they physically couldn't get out.  Having your alarm announce "Fire" is very helpful.
 
So... have a means of temporarily silencing nuisance alarms without deactivating them..
If you have kids have fire drills so they know what to do..
Physically have a way to get out, AND TEST IT.
You can't have too many smoke alarms. Just follow the rules and don't put them in a kitchen or other places where they can cause nuisance alarms. 
 
That 37% should be a wakeup call that having working smoke detectors isn't the end of it.

 

[cobra]

One of the morning national news shows just ran a piece on fire last week.  They showed that construction materials and home furnishing materials are changing in recent years.  As the materials move to artificial fibers (curtains, rugs, sofa materials) the burn rate has increased.  They compared an average living room from 10-20 years ago with a similar room today.  Starting a similar curtain fire, they found that the older construction burned to a dangerous smoke level in 10 minutes or longer.  The newer materials burned in a few minutes, and had more dangerous smoke, leaving the warning time for smoke detectors to a very small margin.
 
The part that surprised me was that it wasn't one item in the newer construction house that caused a problem.  Curtains, carpets, couches, all burned faster and smoked more.

 

[pete_c]

Here had one of the first generation Z-Wave lighting modules do a crash and burn while we were sitting in the family room watching television.
 
The module was behind the couch and the flames from the switch did a number on the exterior of the switch and a little bit on the wall but nothing happened to the couch.
 
It was fast and the nearby smoke detector (X2) did not go off.  Nearby is less than 8 feet away. I had never seen this before with any any automation modules used to date.  I did send pictures to the manufacturer of the switch and it was promptly replaced.
 
Will post pictures that I took of the exterior and take apart.
 
In the 1980's here used a large amplifier and did a bit of remote analogue volume controls stuff.  I had split the audio up from an old stereo Marantz receiver (actually the largest one ever made by Marantz at the time).  I had piped the music from the basement to the living room, dining room and deck and had turned it on for a family BBQ.  It wasn't loud.  A family member noticed smoke coming from the wall / analogue volume control during the BBQ.  I removed it during the BBQ and it was melted and a bit burned.  The smoke did not trigger any nearby smokes at the time either.

 

[Del91574]

@ Ano, That's not a complete picture of what is out there, there's other issues which was just touched upon, however the other part, which is presently being addressed with new code, is the tone of the detector itself. This is why the mandate is coming across for low frequency sounders in new installations. There's plenty of reading out there with regards to what is considered impaired and unimpaired and whether or not someone in a deep sleep would effectively be awoken by a standard sonalert piezo in the detectors on the market within the last 10 years. The other consideration is whether or not the installation was "just" and if the audibles meet the ABN levels (air conditioners and other background noisemakers). Even voice announcements aren't sufficient if you can't rouse the sleeping or impaired party, which was brought up during discussions regarding voice evac systems.
 
 
http://www.systemsensor.com/en-us/news/Pages/Low_Frequency_Requirements.aspx
 
 
The facts are the offgassing and products of combustion are far worse now than in years past and the detectors, no matter what the type, are not going to change that until a multi-criteria unit is installed, which is, unfortunately, not economically feasible in the majority of circumstances and applications, so until it's mandated or the AHJ insists due to false alarms, they're not being installed. Think about it, laser smoke detectors have existed on the market for years, as have aspiration detectors....but how many are installed in a residence? almost zero as a market segment.

 

[Del91574]

Here had one of the first generation Z-Wave lighting modules do a crash and burn while we were sitting in the family room watching television.
 
The module was behind the couch and the flames from the switch did a number on the exterior of the switch and a little bit on the wall but nothing happened to the couch.
 
It was fast and the nearby smoke detector (X2) did not go off.  Nearby is less than 8 feet away. I had never seen this before with any any automation modules used to date.  I did send pictures to the manufacturer of the switch and it was promptly replaced.
 
Will post pictures that I took of the exterior and take apart.
 
In the 1980's here used a large amplifier and did a bit of remote analogue volume controls stuff.  I had split the audio up from an old stereo Marantz receiver (actually the largest one ever made by Marantz at the time).  I had piped the music from the basement to the living room, dining room and deck and had turned it on for a family BBQ.  It wasn't loud.  A family member noticed smoke coming from the wall / analogue volume control during the BBQ.  I removed it during the BBQ and it was melted and a bit burned.  The smoke did not trigger any nearby smokes at the time either.

Usually most analog detectors aren't going to trip until you're at a pretty high obscurity or there's enough smoke to stratify. Nature of the beast, they don't want them to false, yet they also want them to work. Fine balancing act and unfortunately, in a residence, you're never going to have 100% coverage with ample sensitivity. Difference between analog and addressible smart units also.