Replacing Smoke Detectors

[iodeac 138]

The smoke detectors in our house are over 10 years old and they need to be replaced. The old ones are Firex, with a harness that plugs into it from the back. All 5 of them are hardwired into the circuit. We bought some combo fire/carbon monoxide detectors yesterday from Lowes and the mounting and harness are all different, but i think it's a different brand. I guess I assumed they would be universal. I'd really like to avoid redoing all the mounting, I was hoping to just buy some new ones and screw them right onto the plastic. Any ideas?

 

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[freyguy 4,284]

buy the 10yr lithium battery ones

[conVINCEd 21,469]

Buy the ones that won’t randomly go off at 3 a.m.

[Lou 264]

These don't have carbon monoxide, I have separate detectors for that.  I used these when replacing hard wired smoke detectors.  They have wiring harness adapters that make it easy.  Also the battery compartment is on the front so you don't have to remove the smoke detector to change batteries.

 

https://www.homedepot.com/p/Kidde-Firex-Smoke-Detector-Hardwired-with-9-Volt-Battery-Backup-Front-Load-Battery-Door-Adapters-Included-Smoke-Alarm-21029886/100246185

[Gil Bang 25,988]

So, the hardwired detectors are wired so that if one goes off, they all go off. 

You can buy a battery-powered product that does the same thing.  They all link together, wireless. 

[TwiceHorn 31,519]

23 minutes ago, Gil Bang said:

So, the hardwired detectors are wired so that if one goes off, they all go off. 

You can buy a battery-powered product that does the same thing.  They all link together, wireless. 

I think they're wired into the alarm circuit to trigger the house alarms as well as whatever racket the detector makes, and alert the monitoring service/authorities.

That's the way ours are.

There's probably some standardization, but using a different brand, I'm afraid, might trigger the house alarm and there may be jumper settings on the alarms depending on the wiring of the system.

Sometimes, even if you use same brand drop-in replacement, some fiddling has to be done that might necessitate a call to the alarm installer.

Like, I replaced all our CO detectors, snap in, no problem.  There was a jumper in there too that I had to make sure was set correctly.  Then they're supposed to be tested with CO.

Edited February 1, 2022 by TwiceHorn

[Gene Parmesan 4,011]

40 minutes ago, Gil Bang said:

So, the hardwired detectors are wired so that if one goes off, they all go off. 

You can buy a battery-powered product that does the same thing.  They all link together, wireless. 

Hardwired is also tied into your house power so you aren't on battery only.

[Judge Roybeanbag 11,819]

23 hours ago, iodeac said:

 

The smoke detectors in our house are over 10 years old and they need to be replaced. The old ones are Firex, with a harness that plugs into it from the back. All 5 of them are hardwired into the circuit. We bought some combo fire/carbon monoxide detectors yesterday from Lowes and the mounting and harness are all different, but i think it's a different brand. I guess I assumed they would be universal. I'd really like to avoid redoing all the mounting, I was hoping to just buy some new ones and screw them right onto the plastic. Any ideas?

 

Enviado desde mi SM-G973U mediante Tapatalk

 

 

 

If you want to do it easy, get this model:

https://www.homedepot.com/p/Kidde-Firex-Smoke-Detector-Hardwired-with-nine-V-Battery-Backup-Front-Load-Battery-Door-Smoke-Alarm-4-Pack-21029887/202029423?MERCH=REC-_-pipsem-_-100655553-_-202029423-_-N

Then buy these adapters.

https://www.amazon.com/gp/product/B00K2C39I6/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

The detector model is newer, and you will have to replace the bracket, but the new bracket uses the existing screw holes and is slightly larger so covers any paint issues.  You basically loosen the screws a little bit, twist the old mounting bracket off, put on the new one, tighten screws, plug the adapter in and twist on the new unit. I replaced all 10 of the same kind you have in my house a while back and it took maybe an hour.  

They don't have carbon monoxide, but you can buy some a couple of plug-in ones if you need them.

Edited February 1, 2022 by Judge Roybeanbag

[Bernard 879]

I did the same with all of mine three years ago. I can’t give you a how-to, but it was very easy, even though the base plates had to be replaced too. The replacement units I bought all came with several different adapters in each package to match the actual alarm device with the existing wiring in the wall of a 1994-built house.

Bernard

[WhatTheBuck 28,795]

On 1/31/2022 at 8:50 PM, conVINCEd said:

Buy the ones that won’t randomly go off at 3 a.m.

In other words, don’t buy First Alert.

[Dr Fear 1,268]

20 hours ago, Judge Roybeanbag said:

If you want to do it easy, get this model:

https://www.homedepot.com/p/Kidde-Firex-Smoke-Detector-Hardwired-with-nine-V-Battery-Backup-Front-Load-Battery-Door-Smoke-Alarm-4-Pack-21029887/202029423?MERCH=REC-_-pipsem-_-100655553-_-202029423-_-N

Then buy these adapters.

https://www.amazon.com/gp/product/B00K2C39I6/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

The detector model is newer, and you will have to replace the bracket, but the new bracket uses the existing screw holes and is slightly larger so covers any paint issues.  You basically loosen the screws a little bit, twist the old mounting bracket off, put on the new one, tighten screws, plug the adapter in and twist on the new unit. I replaced all 10 of the same kind you have in my house a while back and it took maybe an hour.  

They don't have carbon monoxide, but you can buy some a couple of plug-in ones if you need them.

I can confirm all of this, recently replaced the same older Firex.  They had a different mounting bracket, but the screw holes were in the same place.  My house is only 1800 sq ft., so I didn't bother messing with the communication wire.  I also didn't know they made an adapter and just rewired them, which is no more difficult than wiring a ceiling fan.  The only thing I would add is to buy a premium 9 volt battery so you are not replacing them all the time.

[Your Mom 4,830]

I hate smoke detectors. I’d almost rather risk the house burning down than have them go off every time the oil in the cast iron skillet gets a little warm. 

[TeeDubya 3,362]

Second having separate CO detectors.  CO disperses far more effectively than smoke.  One CO detector per floor is usually plenty for most non-Surly-sized homes (<4000sq).