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General Repairs

How to Test a Carbon Monoxide Detector

Quick Answer

Press the test button to trigger the alarm; replace batteries if it fails, and check the expiry date (usually 5-7 years).

How to troubleshoot How to Test a Carbon Monoxide Detector

Carbon monoxide is a silent killer. This guide explains how to test your CO detector and interpret its warning signals to keep your family safe.

Step-by-Step Fix

  1. Press and hold the test button on the front of the CO detector for 5 seconds.
  2. If the alarm sounds loudly, the unit is working; if not, replace the batteries.
  3. Replace the batteries with new ones and test again.
  4. Check the manufacture date on the back of the unit – if over 7 years, replace the entire detector.
  5. Install the detector at head height in a central location, following manufacturer guidelines.

Common Error Codes

CodeMeaningResolution
End-of-life chirpUnit expiredReplace the entire CO detector immediately.
False alarmHigh humidity or dustClean the unit and ensure it is not near steam or aerosol sprays.

Frequently Asked Questions

How many CO detectors do I need?

At least one on every floor and outside sleeping areas.

Can a CO detector detect smoke?

No, CO detectors only detect carbon monoxide; you also need separate smoke alarms.