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Smart Home Device

Kidde KN-COSM-IBA

9 source-linked failure reports. Most reported: Overheating. Typical failure around 11.5 mo.

Reliability signal — · Early signal · data confidence Low

9 confirmed failure reports

Reliability summary

What is likely to go wrong, when it happens, and how expensive it can be — from source-linked failure reports. Counts are reports in our database, not a population failure rate.

Reliability signal

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9 confirmed failure reports · Early signal · Data confidence: Low

Early signal (9 confirmed reports) suggests shorter ownership before failure (typical 11.5 mo), but that is not enough data for a D or F grade.

Most common issue
Overheating
Typical first failure
11.5 mo
Median of confirmed reports with timing
Median repair cost
—
Reported costs only · market varies
Highest reported repair
—
Not a quote · costs differ by country

What breaks?

Failure types

Click a type in the reports section below to filter.

  • Overheating6 · 66.7%
  • Fire / ignition2 · 22.2%
  • Carbon Monoxide Detectors (712)1 · 11.1%

When does it break?

Failure timing

Months after purchase, using reports that included timing.

What does it cost?

Reported repair costs

Distribution of owner-reported repair costs— not a quote or guarantee. Labor and parts prices vary by country.

No reported repair costs yet for this model.

Median months to failure

11.5

Failure reports

9

View →

Median repair cost

—

Still recommend

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% repaired

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% mfr warranty

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% extended warranty

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% support helpful

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Use these reports as a risk signal, then check current listings before you buy.

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What breaks?

What breaks? · reports

Carbon Monoxide Detectors (712)

Carbon Monoxide Detectors (712)

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20181011-A04AF-2147385061. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: Model kn-cosm-iba. Incident: My Kidde Combo CO Alarm is defective and makes a chipping sound regardless of how many new batteries I use.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

Not stated

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20190416-5810A-2147381529. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: KN-COSM-IB. Incident: Ran a call with 6 Kidde Hardwired Combination CO & Smoke Alarm model number KN-COSM-IB that were chirping end of life 7 years after installation after the home owner replaced the batteries. Recommended the homeowner call Kidde to get information on replacements.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

Not stated

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20141203-F350E-1445481. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: KN-COSM-IB. Incident: While conducting a routine pre-sale home inspection, three same model combination smoke/carbon monoxide alarms failed to activate when the test button was depressed and when canned smoke was sprayed. This same scenario has occurred involving the same model alarms during past home inspections I have conducted.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

Not stated

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

10 months

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20150420-FC71C-2147433574. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: KN-COSM-IBA (21006377). Incident: We had a circuit breaker trip. Upon resetting the circuit breaker, the alarms, both combinations smoke/CO alarms, and the smoke alarms (6 total) went off, and would not shut off. I had to physically remove all 6 alarms from the electrical connections to get them to stop.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

10 months

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20160823-4BCA0-1589688. Matched catalog product: Kidde KN-COSM-IBA. Source model text: KN-COSM-IB. Incident: During pre-sale safety inspections of single and multi-family homes required in the state of Rhode Island, same model hardwired battery back-up smoke/CO alarms have been found to not activate during testing, although the indicator light on each unit remained illuminated showing it to be energized. I've encountered this situation involving the same model alarms on several occasions over the past two years and subsequently filed reports with CPSC at that time. The manufacturer claims that these alarms are supposed to chirp every 30-seconds at the end of their useful life, however, an all cases I've been involved with the residents report these alarms have not done so.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

Not stated

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20141015-C9FFD-1433667. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: KN-COSM-IB. Incident: On October 7, 2014 I went to a single family home located in North Kingstown, RI to perform a pre-sale inspection as required by local regulations. This house has two 110 volt, battery backup, interconnected devices. I went to the bedroom area first, I sprayed a small amount of smoke in the device (Smoke/co), and nothing happened, the green power light was on. I again sprayed a little bit more in the device and nothing happened. I then reached up and pushed the test button and nothing happened. I removed the device to check the date the device was made and found it to be June 2005 and there was a 9 volt battery in it. When I removed the device the power light stayed on after it had been removed from 110 volt power. The same model 110 volt smoke detector in the second bedroom functioned but had a low decibel level when activated. The occupants of this home have lived here since these detectors were installed, and never heard a chirp every 30 indicating they were near end of their functional life.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

Not stated

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Overheating

Fire or Smoke Alarms (702)

9 months

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20150427-87FB0-2147433387. Severity: Incident, No Injury. Matched catalog product: Kidde KN-COSM-IBA. Source model text: P12040 and KN-COSM-IBA. Incident: I purchase 5 Kidde Model P12040 smoke alarms and 2 Model [REDACTED] CO and smoke alarms for an addition I was putting on my house. I had a professional electrician do all the wiring in my house. Shortly after install I started having false alarms. I knew they were false because I have one of each type still install from before the renovation and they were not going off. As they would go off I would remove each one that caused the system to go off. out of the 7 units only one had not gone off within a week. I called kidde customer service to see what was going on. They had me run all kinds of tests on my electrical system. All came back as they should. The final test was simple leaving them not hard wired and putting a battery in. Of course one went off as I expected within 10 minutes. A second was within 20 minutes. Kidde said they would replace the two units, however they never arrived in the mail as they said. After 6 months I still have not received assistance on any of the malfunctioning units. I was forced to return them and buy another brand (first alert). I have them now installed and do not have any false alarms, I have reached the conclusion that the issue lies in their product. A consumer should not have to worry about whether a alarm is real or not. Soon a person will ignore a alarm and it will bite them.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

9 months

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Fire / ignition

Fire or Smoke Alarms (702)

13 months

Government / agencyIndexed Oct 22, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20150601-38C94-2147432478. Severity: Unspecified. Matched catalog product: Kidde KN-COSM-IBA. Incident: After a power failure of 2 - 4 minutes, power (120 volts) came back on and the alarm went off. FIRE, FIRE Verbal alarm and audible BEEP. No smoke present, no fire had occurred and I could not silence alarm. I disconnected alarm from 120 volt source, at which time Alarm stopped. This alarm (Kidde Combo Smoke/CO Alarm #: KN-COSM-IBA) has a battery backup.

UnverifiedEvidence ★★★★☆
View report details

Months until failure

13 months

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

92%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

Fire / ignition

Combination Fire/Smoke Alarm and Carbon Monoxide Detector (714)

19 months

Government / agencyIndexed Oct 16, 2026Source-linkedVerify source — SaferProducts.gov incident

SaferProducts.gov consumer incident report 20220907-6E0B1-3890739. Severity: Incident, No Injury. Product: Kidde KN-COSM-IBA (Kidde Combination Smoke and Carbon Monoxide Alarm, Model KN-COSM-IBA. I do not see a serial number on these alarms but the do have manufacture dates: 2020, Sept. 28,). Incident: On several occasions over the last couple months I have been experiencing multiple false fire alarms and fire alarms chirping. I have replaced batteries in every smoke alarm twice in the last month, cleaned every smoke alarm at least once and some 2 and 3 times but I am still having false alarms and alarms chirping. After reviewing the ratings on the Kidde website for this combination smoke and carbon monoxide alarm it appears there is a wide spread issue with what I am experiencing, false alarms and chirping alarms. In the last 2 weeks my family and I have been woken up in the middle of the night with 2 false alarms, i.e. several loud beeps followed by "FIRE, FIRE, FIRE" several times and then repeated and there was not a fire. We have "experienced" 5 times in the last 2 weeks were 1 of 2 different alarms was chirping. Out of the 7 fire alarms I have installed in the house, 2 have triggered false alarms and 2 have been chirping, one of which also triggered a false alarm. It appears that I have at least 3 bad fire alarms out of the 7. After contacting Kidde this morning they said they will provide me with 3 new alarms to replace the ones I have been having issues with. The part that really makes me mad is they said it will take 10 to 15 days or possibly more and when I asked them what I should do until the new alarms arrive I was advised to remove the troublesome alarms by disconnecting them from the house power and remove the batteries. Doing this would remove the ability to possibly detect a fire in these locations with the smoke alarms removed!!! That is if they even wor

UnverifiedEvidence ★★★★☆
View report details

Months until failure

19 months

Repair cost

Not stated

Repaired

Not stated

Manufacturer warranty

Not stated

Extended warranty

Not stated

Support helpful

Not stated

Would recommend

Not stated

AI extraction confidence

88%

Verification status

Unverified

Evidence quality

★★★★☆ (4/5)

Discussion

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