On Mon, 30 Nov 2020 07:39:52 -0500, Frank "frank wrote:

On 11/30/2020 5:20 AM, Dean Hoffman wrote:
On 11/29/20 10:07 PM, Sid 03 wrote:
Looking to install some new smoke detectors.* I was going to install
Ionization type smoke detectors in the lower floors and then a
combination* smoke and CO* detector on the 3rd floor where the
bedrooms are located.

I noticed that most of the combo detectors do not use ionization to
detect smoke, but use photoelectric type sensors.
Is this a a big deal or should I stick with the most popular
ionization type ?
Years ago I was told by a contractor to not install combo detectors,
but to keep the CO and Smoke detectors separate ?
Does anyone have an opinion on that ?

If the CO detector has an interconnection wire for other alarms,
should you connect it to the interconnection wire for the fire-Alarms ?
All this stuff is manufactured by Kidde, so I am assuming that is all
compatible ?

Thanks
Sid.

******** This is what Consumer Reports has to say.* They haven't tested
them for a couple years.

**** This is as of* June 2018.

***** Consumer Reports wasn't satisfied with any combination
smoke and carbon monoxide detectors they tested then.

** These are the dual sensor smoke alarms.
First Alert* 3120B*************************************** $30** Score 91
Kidde P12010******************************************** * $30** Score 91
First Alert SA320CN********************************** $23** Score 87
Kidde P19010******************************************** * $25** Score 87

* Ionization smoke alarms.
First Alert SA9120BCN****************************** $25 Score 55
Kidde KN-COSM-1B********************************** $35 Score 55** Note 1
Kidde RF-SM-DC*************************************** $40 Score 53
First Alert SA303**************************************** $12 Score 51
First Alert SA304LCN******************************** $24 Score 51

Photoelectric smoke alarms
First Alert 7010B***************************************** $25 Score 55
Nest Protect******************************************* ****** $129 Score
55*** Note 1,2
Nest Protect******************************************* ****** $129 Score
55*** Note 1,2
First Alert* SA501CN********************************* $60* Score 53 Note 2
First Alert* SC051CN********************************* $70* Score 53 Note
1,2

1 Combination smoke/carbon-monoxide alarm, also rated as CO alarm.
2 Interconnects wirelessly.



I knew that CO detectors had a finite lifetime, 7-10 years, and now note
that smoke detectors are recommended to be replaced by 10 years. Still
not sure a combo appeals to me since I got over 20 years out of two
smoke detectors before I replaced them.


I think the 10 year "lifetime" is a recommendation that will
provide acceptable reliability - beyond that, the device
may still be OK but the crucial reliability begins to decrease.
I'd be OK stretching it to 12 years, not 20.
John T.