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USI Electric MICN109 Ionization Review

Editor's Note: This review has been removed from our side-by-side comparison because it no longer ranks as a top 10 product.

Our Verdict

The combination smoke, CO and natural gas detector covers a wide range of potential hazards, but its seven-year warranty indicates it may not last as long as competing brands.

For

  • It can be interconnected with as many as 24 USI brand devices.

Against

  • The manufacturer warranty is only seven years, compared to other brands that offer 10-year warranties.
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USI Electric MICN109 image: This smoke detector combines an ionization sensor and a carbon monoxide and natural gas detector.

USI Electric MICN109 image: This smoke detector combines an ionization sensor and a carbon monoxide and natural gas detector.
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USI Electric MICN109 image: If you use appliances that burn fuel, it is recommended to install one CO alarm on every level of your home.

USI Electric MICN109 image: If you use appliances that burn fuel, it is recommended to install one CO alarm on every level of your home.
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USI Electric MICN109 image: Potential sources of CO include fuel-burning appliances, fireplaces and attached garages.

USI Electric MICN109 image: Potential sources of CO include fuel-burning appliances, fireplaces and attached garages.
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USI Electric MICN109 image: Backup battery power is provided by a single 9-volt battery.

USI Electric MICN109 image: Backup battery power is provided by a single 9-volt battery.
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USI Electric MICN109 image: The alarm sounds at a standard 85 decibels.

USI Electric MICN109 image: The alarm sounds at a standard 85 decibels.
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USI Electric MICN109 image: Front-located LED indicators tell you the source of a hazard.

USI Electric MICN109 image: Front-located LED indicators tell you the source of a hazard.

Editor's Note: This review has been removed from our side-by-side comparison because it no longer ranks as a top 10 product. The original review is below, but check out our current top 10 about Smoke Detectors here.

The USI Electric MICN109 is a hardwired smoke detector that connects directly to your home’s electrical system and switches to battery backup in the event of a power outage. It also comes with a built-in carbon monoxide (CO) and natural gas detector.

Equipped with an ionization sensor, the USI Electric MICN109 can detect flaming fires better than it can detect slow-burning, smoldering hazards. The best smoke detectors come with dual-sensor capability, coupling ionization and photoelectric sensors that enable the most effective detection of both types of fires. When using the MICN109, consider installing photoelectric smoke detectors at intervals throughout your home for best protection.

This smoke detector also comes equipped with a combination CO and natural gas detector. Depending on the types of appliances in your home, you may not need a CO detector or a natural gas detector. Homes with appliances that have fuel-burning appliances, fireplaces or attached garages may benefit from the installation of a CO detector, as carbon monoxide is odorless. A natural gas detector may also not be required if your home does not have gas appliances.

The MICN109 connects directly to your home’s electrical system and switches to battery backup when the power goes out. For this reason, you can expect to not have to replace batteries as frequently as you would if you had a wireless smoke detector. As a rule of thumb, it is recommended to replace your backup batteries at least once every 12 months.

When the backup battery begins to run low, the MICN109 will emit a brief chirp every 40 seconds until the battery is replaced. An LED light on the face of the device will also flash once every 20 seconds to provide visual notification.

One of the benefits of hardwired smoke detectors is that they can be interconnected to one another. This means that when one alarm is tripped, all of them sound off. Smoke alarms that are not interconnected can be more difficult to hear, especially if the source of the fire, CO or gas leak is located in a basement or a detached structure. A series of LED indicators on the unit indicate if the alarm was set off by smoke, CO or natural gas. A button on the front plate of the smoke alarm can be pressed to silence the alarm. This button is also used to test the alarm’s function. This smoke detector can interconnect with up to 24 devices, with a limit of 11 smoke alarms.

Unlike most smoke detectors that come with 10-year warranties, the MICN109 comes with a seven-year warranty. Online troubleshooting is limited, and the only available support channel provided is via telephone.

The USI Electric MICN109 provides peace of mind. To maximize its usability, consider installing this unit in combination with other photoelectric smoke detectors or purchasing a dual-sensor model with ionization and photoelectric capabilities.