Smoke detectors, Ionization vs Photoelectric

[Transition Zone]

On Monday, November 30, 2020 at 7:40:03 AM UTC-5, Frank wrote in alt.home.repair:
> 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.

Its easy to forget and just leave the detector in place.