First Alert CO606 Plug-In CO Alarm with 9V Battery Backup Review (4.1/5) | WC Safety
First Alert CO606 Plug-In CO Alarm with 9V Battery Backup Review
Model CO605XP | Reviewed by Steve Thompson | WC Safety
Bottom line: The CO606 is First Alert's simplest plug-in CO alarm it plugs into a wall outlet, runs on AC power, switches to 9V battery backup when the power goes out, and sounds an 85 dB alarm when CO is detected. No display, no interconnect, no extra features. If you want the lowest-cost plug-in CO alarm that also covers power outages, the CO606 covers that. One critical note: always choose the CO606 over the CO600 the CO600 has no battery backup at all, which is a significant safety gap for a nominal price difference.
Pros
- AC plug-in continuous power, no battery swap for operation
- 9V battery backup works during power outages
- 85 dB alarm audible throughout home
- Single-button test and silence operation
- UL 2034 listed
- 7-year limited warranty
- Low price budget-accessible CO protection
Cons
- No digital display no PPM readout
- No wireless or wired interconnect
- Plugs directly into outlet placement constrained by outlet location
- 9V backup battery requires annual replacement
- No voice alert
How we evaluate CO alarms: We assess power reliability, backup coverage, UL certification, warranty coverage, and value. Entry-level alarms are evaluated on whether they deliver code-compliant protection reliably not against premium features they don't claim to have.
Verdict: 4.1 / 5
The CO606 does exactly what it advertises at an entry-level price: plug-in AC operation with 9V battery backup and a UL 2034-listed 85 dB alarm. For budget-conscious buyers who need reliable plug-in CO coverage without display features or interconnect, the CO606 is a sound choice. Step up to the CO615 if a digital PPM display and 6-foot cord matter to you; step up to the CO511 if wireless interconnect is a priority. Do not choose the CO600 over the CO606 the lack of backup on the CO600 is a meaningful safety gap that the CO606 eliminates for a small price difference. View the CO606 at WC Safety or Check Price on Amazon →.
| Specification | CO606 (CO605XP) |
|---|---|
| Power source | 120V AC plug-in |
| Battery backup | 9V alkaline battery |
| Display | None |
| Alarm output | 85 dB |
| UL listing | UL 2034 |
| Interconnectable | No |
| Sensor type | Electrochemical |
| Warranty | 7-year limited |
Frequently Asked Questions
Does the CO606 have a digital display?No. The CO606 has no digital display and no PPM readout. It provides an 85 dB audible alarm when CO reaches UL 2034 alarm thresholds but shows no visual CO level. If a display for monitoring CO concentration is important, step up to the First Alert CO615 (plug-in with 6-foot cord, AA backup, and digital display) or CO615.
No. The CO606 has no digital display and no PPM readout. It provides an 85 dB audible alarm when CO reaches UL 2034 alarm thresholds but shows no visual CO level. If a display for monitoring CO concentration is important, step up to the First Alert CO615 (plug-in with 6-foot cord, AA backup, and digital display) or CO615.
Does the CO606 work if the power goes out?Yes. The CO606 uses a 9V battery backup that activates automatically during power outages. This is an important feature many CO events occur during outages when generators, gas grills, or propane heaters are used indoors. The backup battery should be replaced annually to ensure it's fully charged when needed. This is the key advantage of the CO606 over the no-backup CO600.
Yes. The CO606 uses a 9V battery backup that activates automatically during power outages. This is an important feature many CO events occur during outages when generators, gas grills, or propane heaters are used indoors. The backup battery should be replaced annually to ensure it's fully charged when needed. This is the key advantage of the CO606 over the no-backup CO600.
How does the CO606 compare to the CO600?The CO600 is an AC-only unit with no battery backup. The CO606 adds a 9V battery backup for power-outage coverage. In residential settings, the CO606 is almost always the better choice outage protection is critical for CO alarms, particularly during storms and winter weather events when alternative heat sources are commonly used. The CO600 is appropriate only for commercial or institutional locations where power is guaranteed by a UPS or backup generator.
The CO600 is an AC-only unit with no battery backup. The CO606 adds a 9V battery backup for power-outage coverage. In residential settings, the CO606 is almost always the better choice outage protection is critical for CO alarms, particularly during storms and winter weather events when alternative heat sources are commonly used. The CO600 is appropriate only for commercial or institutional locations where power is guaranteed by a UPS or backup generator.
How does the CO606 compare to the CO615?The CO615 adds three things the CO606 lacks: a 6-foot power cord (instead of plugging directly into the outlet), AA battery backup (longer-lasting under load than 9V), and a backlit digital display showing real-time CO PPM. The CO606 is the budget option for buyers who need plug-in CO coverage without extra features. The CO615 is the mid-tier option adding placement flexibility and display monitoring at a higher price.
The CO615 adds three things the CO606 lacks: a 6-foot power cord (instead of plugging directly into the outlet), AA battery backup (longer-lasting under load than 9V), and a backlit digital display showing real-time CO PPM. The CO606 is the budget option for buyers who need plug-in CO coverage without extra features. The CO615 is the mid-tier option adding placement flexibility and display monitoring at a higher price.
Where should I install the CO606?Install the CO606 in an outlet per NFPA 720 guidelines: on each level of the home and within 10 feet of each sleeping area. Because the CO606 plugs directly into the outlet (no power cord), its placement is determined by where outlets are located. Avoid outlets behind furniture or below 1 foot from the floor. If the available outlet location is not ideal, the CO615's 6-foot cord offers positioning flexibility.
Install the CO606 in an outlet per NFPA 720 guidelines: on each level of the home and within 10 feet of each sleeping area. Because the CO606 plugs directly into the outlet (no power cord), its placement is determined by where outlets are located. Avoid outlets behind furniture or below 1 foot from the floor. If the available outlet location is not ideal, the CO615's 6-foot cord offers positioning flexibility.
Is the CO606 interconnectable with other alarms?No. The CO606 is a standalone plug-in alarm with no wired or wireless interconnect capability. If whole-home simultaneous alerting is needed, the CO511 is the First Alert wireless interconnect option (battery-powered). For hardwired interconnected systems, look at First Alert's hardwired interconnectable models.
No. The CO606 is a standalone plug-in alarm with no wired or wireless interconnect capability. If whole-home simultaneous alerting is needed, the CO511 is the First Alert wireless interconnect option (battery-powered). For hardwired interconnected systems, look at First Alert's hardwired interconnectable models.
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