First Alert CO600 Plug-In AC-Powered Carbon Monoxide Alarm

Short answer: The CO600 is First Alert's plug-in AC-powered CO alarm — permanent, no battery maintenance, designed for locations with a reliable outlet. The tradeoff versus the CO606 is that the CO600 has no battery backup, meaning a power outage during a CO event would cut power to the alarm. For most permanent home installations where power outages are infrequent, the CO600 is solid. For peace of mind during outages, step up to the CO606.

CO600 vs CO606 — Do You Need Battery Backup?

CO Poisoning Risk and Why Placement Matters

Carbon monoxide is produced by any fuel-burning appliance — gas furnaces, water heaters, generators, fireplaces, and vehicle exhaust. CO is colorless and odorless and at moderate concentrations causes symptoms that mimic the flu: headache, dizziness, nausea. At high concentrations it causes loss of consciousness and death. The CO600 is rated to alarm before CO reaches dangerous concentration levels in normal residential exposure scenarios.

• Install on each level of the home and outside each sleeping area
• Place 5 feet above floor level — CO is slightly lighter than air and disperses throughout the room
• Avoid kitchens, high-humidity areas, and locations near furnace vents

Frequently Asked Questions

Will the CO600 work during a power outage?

No — the CO600 requires 120V AC and has no battery backup. During a power outage, the unit will not function. This is a critical consideration because power outages often coincide with increased CO risk from generators and alternative heating sources. If outage protection is important, choose the CO606 instead.

Does the CO600 detect smoke or natural gas?

No — the CO600 detects carbon monoxide only. It will not alarm for smoke, propane, natural gas, or other hazards. Install separate smoke alarms and consider a natural gas/propane detector if applicable.

How long does the CO600 last?

First Alert rates the CO600 for a 7-year service life. The electrochemical sensor degrades over time and the unit emits an end-of-life signal (distinct from the alarm pattern) when replacement is needed. Do not attempt to extend use beyond the rated service life.

Is the CO600 sufficient to meet code requirements?

The CO600 is UL 2034 listed, which is the standard referenced by NFPA 720 and most state CO alarm codes. However, check local requirements — some jurisdictions require battery backup or interconnected alarms in new construction.