Replace Residential Smoke Alarms Every 10 Years (AC-Interconnected Guide) - Avenger Security

Replace Residential Smoke Alarms Every 10 Years (AC-Interconnected Guide)

Home smoke alarms don’t last forever. Most manufacturers specify a service life of about 10 years. For code-aligned safety, replace AC-powered, interconnected smoke alarms with listed new units and retain battery backup. Always confirm local requirements with your Authority Having Jurisdiction (AHJ).

Why replace at ~10 years?

  • Sensor drift & dust: Sensitivity changes over time, increasing nuisance alarms or missed detection.
  • Components age: Chambers, sounders, and power supplies degrade.
  • Listing & warranty: Manufacturer end-of-life guidance typically calls for replacement at 10 years.

What to replace with

  • AC-powered, interconnectable alarms (120 VAC) with backup battery (replace 9V or use sealed 10-year if compatible).
  • Photoelectric (common for smoldering fires); consider dual-sensor or combo Smoke/CO where allowed.
  • Listed & compatible models when mixing brands—follow the manufacturer’s interconnect compatibility list.

Replacement basics (summary)

  1. Power off the circuit at the breaker and verify.
  2. Label date on each new alarm (month/year) and record locations.
  3. Connect harness: Hot (usually black), neutral (white), and interconnect lead (often red/yellow)—match per the device instructions.
  4. Restore power, then test interconnect so one alarm activates all.
  5. Maintenance: Vacuum the alarm face 2–4×/year and test monthly.

Where alarms belong (typical residential)

  • Inside every bedroom and outside each sleeping area.
  • On every level of the home, including the basement.
  • Follow placement clearances from kitchens, bathrooms, registers, and fans per the device manual and local code.

Video: Replacing aging alarms

Demonstration: replacing older residential smoke alarms and testing the interconnect.

When to call a pro

  • You’re unsure about wiring or interconnect compatibility.
  • You’re adding combo Smoke/CO or integrating with a monitored security/fire panel.
  • You need placement guidance for renovations, additions, or code changes.

Need help selecting listed replacements or tying AC alarms into a monitored system? See our Fire & Life Safety services or request a visit.

Safety note: De-energize circuits before working. Follow manufacturer instructions and confirm requirements with your AHJ.

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