Nest Protect Installation Question

Hello everyone,

I’m planning to install the Nest Protect in my home. At my home i already have Nest Thermostat & Nest cam. Recently i got the Nest Protect on a deal.

my home is new construction. The builder had setup kiddie smoke detectors. I have about 6 of them wired together.

My question is since all of my 6 existing kiddie smoke detectors are interconnected, can i install the one nest protect which i got it and link it with the other 5 smoke detectors. Is this recommended setup for nest protect ? For the people who have installed nest protect at home pls share some tips.

Thanks in advance.

The answer is Nest protects only connect to other Nest Protects and not to other smoke detectors. Nest Protect connects wirelessly using the Wi-Fi 802.11b/g/n protocol and 802.15.4. It uses both connections together to create reliable, flexible, secure and low-power communication between Nest Protects.


Thanks @jkp In my case if i had to replace my smoke detectors with nest protect then do i have to do replace all 6 of the wired smoke detectors with the nest protect ?

If you want all 6 to go off when one detects a problem, then yes. Otherwise is the Protect senses the problem, only it goes off. If one of the other 5 detect it, those 5 go off but not the protect.


Thank you. I got it your point now. I thought i will try with one first and then decide if i want to replace all of them.

My current kiddie smoke detectors always get the chirping noises often & wakes us in the middle of the night. we already have this chirping noises in 3 smoke detectors. This is the reason i was thinking if replaced it with the nest we can control it via the smartphone.

I know this is a personal choice question, Do you think its worth it to replace all 6 of them with the nest protect?

Since already has hardwired Kidde, I doubt changing batteries is an issue. Almost all current generation battery powered smoke detectors come with built in long life batteries that do not / can not be replaced. Once they die you throw the whole thing away and buy a new one. Before I updated/upgraded to protects over the last few months I had a mix of hardwired and battery powered Kidde. The battery powered are 6 years old and on the original batteries.

Again current generations do not have replaceable batteries, and if Nest battery or even battery backup on hardwired units get low it will still annoy the dung out of you.

Well pretty sure any thermostat would shut off heat during a fire, well unless your thermostat is set for 500* or something.

So long as your current Kidde run on 120 ( assuming they do, I know mine do ) you can direct replace them with Nest Hardwired units. Just change the wire adapter ( after cutting power to the circuit of course ) and ignore the traveler wire since Nest communicate with each other wirelessly . Attach the nest mounting plate to the current box .

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Thanks @RLDreams & @jkp . Appreciate the information you have shared.

Can we mix the Nest protect battery and wired versions since they communicate via wifi anyway ? Is there any advantages over the other ?

Yes you can . Building codes vary, but around here they requires hardwired Smoke & CO2 detectors by furnace , water heater etc. Battery powered are fine for living areas. So I have 2 Hardwired Protect in basement by furnaces and water heaters, just installed 2 more hardwired in sunroom where I installed a pellet stove ( drop ceiling so easy access to run Romex to power them. I have battery powered Protects in living, dining rooms and upstairs bedrooms. They all work seamlessly together.
Only real advantage of one over the other is that you can put battery powered in places you don’t have ( easy ) ability to run wiring. They both work exactly the same. You can usually find a sale on the hardwired units more often than on the battery powered ones. ( Last week some Lowe’s stores had hardwired units on sale for $49 ) I rarely see sales on the battery powered units.

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Thanks @RLDreams . This is helpful.

Since these nest protects communicates each other through wifi , what happens when there is no wifi or when there is power failure at home ? Will all 3 of the Nest products i.e. nest thermostat, nest cam and nest protect communicate each other in this situation?

If your power is off the Nest cams will be off. Not sure about the thermostat as they have battery but the HVAC system(s) will be off anyway with no power. Protects will fall back to battery and continue to work on their own. They will communicate with the other Protects using battery power I believe but I am not 100% certain. I would think yes as with the battery power only version they communicate with each other without mains power.

This will explain how they communicate:

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Thank you @tonesto7 for sharing this information.

I am also considering purchasing a Nest Protect. Question, though - do I have to have the Nest thermostat for the Protect to work? Or will they connect separately to the SmartThings hub?


Hi, No need to have other Nest products… I only got 2 nest protect… using @tonesto7 Nest Manager smartapp and DH, it just works great with ST!!

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