I just bought a set of Nest Protects and after opening the first one I noticed that its manufacture date was almost a year ago and that the expiration date was 10 years from the manufacture date, not from the install date. So effectively the units cost 10% more than their list price.

My reading of the Nest Protect manual is that the units will start nagging you to replace them a couple of weeks before the expiration date and that they will become quite insistent once they "expire."

A call to Nest wasn't too productive, but I did learn that:

  • I shouldn't expect the Protects to last 10 years - more like 7 or 8.
  • They actually start counting the 10 years from the install date - but supposedly this doesn't show up in the app. If I want to check the expiration date I can look at the back of the unit… Hopefully what they mean is that I can calculate it myself from the install date that I can write in the space that they provide.
  • That if I want to get fresh units I can have the store open them up for me to check the expiration dates (they are not printed on the outside of the packaging).

Needless to say I'm underwhelmed by the quality of the support.

Does anybody know:

  • If the date does show up in the app?
  • If it does, is it recalculated based on the installation date?
  • How the Protect behaves when it reaches its expiration date?
  • The typical age of units in stores (i.e., is the retail pipeline really almost a year long)?
  • Sources that are likely to have fresh stock?

Thanks. I think I still like the units, but would sure appreciate better customer support.

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    We are not customer support so we can not help with that. Fresh stock? you will have to ask each retailer. Pipeline? you will have to ask someone knowledgeable about supply logistics. Has this unit been in existence long enough that anyone has reached the life span of the product ? – Alaska Man Jun 26 '19 at 19:07
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    I was hoping that there would be enough experience here to answer some of the questions, perhaps someone has installed a bunch and usually gets ones that are several months old. Or has looked at the app and knows that it does, or doesn’t, report the replacement date. – dlu Jun 26 '19 at 19:23
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    Wait. Isn't this thing a smoke detector? – Harper - Reinstate Monica Jun 26 '19 at 19:34
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    Yes, it is. Why? – dlu Jun 26 '19 at 19:36
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    @Harper-ReinstateMonica It's a more advanced smoke detector than just an americium one, and includes a carbon monoxide detector and motion-sensor night light too, so it's "only" about $100 extra for it to include mobile phone notification via the internet (as long as the router didn't start the fire). The expiration date applies to the CO detector for technical reasons. – Andrew Morton Dec 28 '19 at 18:59

As you can see mine shows replace by April 2026 although I didn’t buy them until end of Aug 2018 and fitted them a couple of months later. I’d better start saving up for the next ones now!

enter image description here

So i didn’t get the full product at a discounted price, simply received a reduced lifetime at a higher prorata cost :(

Can’t tell you about the end of life nagging but i suggest all potential customers wait till my 2026 expiry, when i will be able to give clarity. before buying unless Nest want to answer your question sooner?


All smoke detectors and CO detectors have 10-year life spans. It is related to the manufacture date - it doesn't matter when you install it.

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    I understand why CO detectors and alarms have a 10year life limit (it's the shelf life of the CO sensor inside, basically), but why do smoke alarms have such a life-limit, save for "sealed battery" types of course (where the life limit is governed by battery self-discharge, and is probably going to be longer than 10 years on average)? My understanding, reinforced by the smoke detector at our house (a circa 2003 single-station type, presumably ionization) that faithfully reports on the smoke signals the oven sends out, is that the actual sensor in a smoke alarm isn't limited so... – ThreePhaseEel Aug 12 '20 at 22:58
  • They have expiration dates because of regulatory capture. It is simultaneously to ensure safety, but also to ensure that people purchase new products from the manufacturer on a regular basis! – Jason Aug 13 '20 at 2:59

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