First Alert GCO1CN Explosive Gas and Carbon Monoxide Alarm
- Power Source: Corded Electric
- Sensor Type: Electrochemical
- Alarm: Audible
- Operating Humidity: 10-95% RH
Last refreshed Sep 8, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
The step-up First Alert plug-in for homes running gas or propane, since it reads three hazards instead of one and keeps monitoring on battery through an outage.
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ASIN: B000H2651YModel: GCO1CNCategory: Carbon Monoxide Detectors
Overview
A plug-in combination alarm that adds explosive gas detection, propane and methane, to First Alert's carbon monoxide sensing, with a backlit digital display and 9V battery backup.
Where the CO600 is CO only, the GCO1CN covers three hazards from one outlet: carbon monoxide plus propane and methane gas. The digital display shows current and peak readings rather than a simple pass or fail alarm, and it can be muted from an existing household remote.
- 3-way CO, propane and methane detection
- Backlit digital display with peak readings
- 9V battery backup
- Remote-mute capable
Who it's for
Households with gas appliances, propane tanks or a gas furnace who want combustible gas detection alongside CO, not CO alone. Less useful in an all-electric home with no gas or propane source.
Pros and cons
- Detects propane and methane alongside CO
- Backlit display shows current and peak readings
- 9V battery backup covers power outages
- Can be muted with a household remote
- Costs more than a CO-only plug-in unit
- Battery backup covers this unit only, not a smoke-alarm role
Performance notes
The unit reads carbon monoxide with an electrochemical sensor and tracks combustible gas separately, showing both current and peak levels on the backlit display rather than only tripping at a threshold. The 9V battery backup keeps it monitoring through a power outage, and remote mute lets you silence it without reaching the outlet.
Specifications
| Brand | First Alert |
|---|---|
| Model | GCO1CN |
| Dimensions & fit | |
| Item Dimensions D X W X H | 2.5 × 7 × 5 inches |
| Power & efficiency | |
| Power Source | Corded Electric |
| Construction & materials | |
| Color | Gray/White |
| Included components | |
| Unit Count | 1 |
| Warranty & support | |
| Manufacturer Warranty Description | Limited Ten Years |
| Other details | |
| Sensor Type | Electrochemical |
| Alarm | Audible |
| Operating Humidity | 10-95% RH |
| Number Of Items | 1 |
| Product Style | Digital |
| Mfr Part Number | GC01CN |
| Builtin Media | Electrical & Heating;Security And Intrusion Monitoring;combination-Smoke-Carbon-Monoxide-Detectors |
| Item Type Name | Plug-In Combination Gas Detector, Co, Natural/Methane, Propane, Low Battery |
| Item Highlight | GCO1CN With Digital Display And 9V Battery Backup |
Frequently asked questions
What gases does the GCO1CN detect besides carbon monoxide?
It also senses propane and natural or methane gas, covering three hazards from one plug-in unit.
Does it work during a power outage?
Yes, an included 9-volt battery backup keeps it monitoring if the outlet loses power.
Can I silence it without touching the unit?
Yes, it can be muted remotely using almost any household remote control.