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Smoke & CO2 Detectors 101: Home Safety Essentials

As a provider of Home Watch services, I find myself frequently replacing batteries in smoke and CO2 detectors monthly for my various clients. I adhere to the following Home Watch Best Practices for smoke detectors and CO2 detectors in my clients' homes, and they consistently approve of my recommendations for their homes safety.

While there's a wide variety of models on the market, I can share some general insights that apply to most of them.

Battery Types:

  • Regular 9-volt battery (most common)

  • U9VL-X (10-year Ultra Life 9-volt)

  • 123A Lithium battery (common, 10-year life)

  • AA batteries (older units, less common)

  • AAA batteries (older units, less common)

Battery Replacement Cycle:

It's good practice to replace all batteries when one starts beeping to ensure they all have a similar lifespan. This reduces the likelihood of being disturbed by chirping alarms in the middle of the night also.

Battery-only vs. Battery Backup:

If your smoke alarm has wires coming from the ceiling (generally a 3 pin prong on detector), this means it runs on electrical from the home and the battery in the unit is actually a battery backup if the power goes out.

Detector Unit Replacement:

The industry actually recommends replacing each detector every 5 years. The reason being is that the detector intake (where it samples air from for readings) will eventually get a layer of grime from the normally occurring air in the home and this will stop it from being 100% accurate in reading and ability. 

  • When selecting new devices, opt for mid-range priced units with basic features, as they will need replacing in 5 years anyway. Avoid expensive 10-year batteries, as they are not cost-effective considering the unit replacement cycle.

  • Ensure you have both CO2 and smoke detectors, especially in sleeping areas. If your home is wired for detectors, utilize the home wiring for an additional layer of protection against power loss. Be safe!

Chirp, chirp, chirp!



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