I have 2 of these smoke detectors in my house. They don’t have any information on them to indicate the brand or model. I did do a reverse image search on Google which came up with Sensaphone IMS-4862, but even that information got me nowhere; I can’t find an instruction manual, and I even spoke with Sensaphone customer support who didn’t know how to help.

Basically I just want to test the alarms and replace batteries if needed. But I don’t even know if they have batteries or if they’re only hardwired. There is a spot on the edge that says “Test” but there’s no button to press, so it’s unclear how to conduct the test. I’ve tried twisting the front of the unit in both directions and nothing comes off. I’ve tried twisting the entire unit from the ceiling in both directions and nothing comes off.

Really at a loss here and just want to make sure our smoke detectors are operating as intended. If anyone can help I would appreciate it!

For reference, the house was built in 1999 and these may be original. We moved in 8 months ago.

After having discovered that the detectors are tied in to the old security system, I’ll hopefully be able to use the information on the security system control box to track down how to replace the detectors themselves. Thanks!

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    The expiration date would be on the bottom. You/we need to figure out how to take it down.
    – DoxyLover
    Jul 21, 2023 at 13:18
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    Having just pulled one of mine, the ‘issue’ date is on the side of the detector up against the ceiling. Many rotate counterclockwise to come off their mounting bracket. Get it off and see if there is a date on it. Expiration is 10 years after manufacture. (I’m a big fan of the ones with 10 year batteries, your mileage may vary.)
    – Jon Custer
    Jul 21, 2023 at 13:21
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    @Huesmann I think you’re on to something with the security system. There’s a control box for our home’s original (but inactive) security system that I’ve just looked at, and it has some labels for smoke detectors. It also has a backup battery in the control box, which I’m wondering if that is meant to serve the smoke detectors. Unfortunately the battery isn’t connected to anything, and there are a ton of wires floating about. Gives me a good lead though for finding out more info, so thank you.
    – Anna
    Jul 21, 2023 at 13:46
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    While the battery is one concern, the potentially bigger one is the sensor. Many (most these days) use a radioisotope source, and those decay with time. They are designed for a 10 year life and may not detect smoke after that, whether the battery works or not.
    – Jon Custer
    Jul 21, 2023 at 13:53
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    If the security system is inactive, the smoke detectors associated with it may also be, aside from all the out-of-date potential issues.
    – Ecnerwal
    Jul 21, 2023 at 17:23

4 Answers 4


This detector housing is fairly generic - I've seen a few brands that all use very similar designs (probably all manufactured by the same company). As discussed in the comments, the ones I know of are typically connected to a security system.

Detectors that have the word "test" without a button may use a magnet for testing instead. Inside the housing behind that word, there is a reed switch that is activated by holding the magnet next to the switch. (I have a few that are like this.)

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    Thanks for the tip about the magnet! The previous owners actually did leave a little bag of magnets near the security system housing. I never thought the two could be related! After holding the magnet up, if it sounds the alarm, will it stop when I take the magnet away? I’ve never tested an alarm that didn’t have a button.
    – Anna
    Jul 21, 2023 at 15:04
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    @Anna Either it will stop when you take the magnet away, or it needs to be cleared from the security system control panel. Without knowing your specific system, I can't answer that for sure.
    – Moshe Katz
    Jul 21, 2023 at 16:19
  • @Anna -- if the alarm doesn't stop sounding when you take the magnet away, then you'll have to clear it from your alarm panel. Furthermore, if you have a central alarm panel, you'll need to change the batteries there, rather than at the smoke detectors/alarms (unless it's a wireless panel, ofc) Jul 22, 2023 at 1:48

As noted in the comments, these are almost certainly well outside their 10 year lifespan.

Pull them down by whatever means necessary (they’re just plastic, so the mounting points will break if needed), figure out if they’re hardwired (ie, supplied with 120 volts AC) or battery and go shopping.

Check local regs for disposal guidelines. Some places don’t want these in the normal waste stream.

There should be lots of information here about installing new ones, if needed.

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    If it's part of the security system, and if you are paying monthly maintenance fees for that, they can and should replace it, for free, and probably with a wireless one with a 6 year battery.
    – jay613
    Jul 21, 2023 at 15:55

If the word "test" is printed on them, somewhere near that is a button you can push to test them. If they respond to that button, they're working. If not, they are dead or need battery replacement or both.

I can't tell from the photo how to access the battery in this one, but some possibilities:

Some have a battery compartment that flips open when you push a catch up or a battery drawer that swings out or slides out.

For others, the cover opens; in that case generally twist counterclockwise (like a screw) to remove. There may be a tamper-deterrent mechanism that has to be released first, such as a latch to be squeezed or a pin or screw to be removed. Or they may simply be stuck, possibly with paint.

Some units sold in the past few years came with batteries intended to outlive them. For anything older, or which hasn't already been fitted with one if these ten-year-life batteries, if the battery is older than a year it needs to be replaced; if it hasn't died yet it will soon. Newer units may chirp at you when the battery starts failing, but that only lasts until the battery dies completely.

Current recommendation is that the entire smoke detector has a maximum life span of ten years and should be replaced after seven. So if these may be older than that the safest thing to do is just replace them rather than wrestling with testing and batteries. New units, again, have started beeping at around 7 years to remind owners to do this; old ones just became ineffective.


Some detector's test circuits are activated by really bright lights - try shining a flashlight/torch at the open holes in the bottom face.

This is done so high-mounted detectors can be tested from the floor by a bright light rather than climbing a ladder to press a button.

You may need to tape a torch to a pole like a broom handle to get close enough.

However if the detectors do date from 1999 they're well past replacement date. 10 years after manufacture is the cutoff. Expect to just replace them all.

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