Smoke and CO detectors: chirping, false alarms and upkeep
Smoke and CO alarms are the cheapest safety gear in the house, and most trouble with them is simple. A chirp every 30 or 60 seconds is usually a low battery or an alarm that has worn out, and an alarm that goes off with no fire is usually a false alarm from cooking smoke, steam or dust. Don't disable an alarm to quiet it, and if a CO alarm sounds, get outside and call 911.
- Smoke detector chirping?A smoke or CO alarm that chirps every 30 or 60 seconds, usually a low battery, a worn-out alarm, or a battery drawer that isn't fully closed.
- Smoke detector false alarm?A smoke alarm that goes off with no fire, usually cooking smoke or steam nearby, dust or insects, or an aging sensor.
Typical lifespan: 10 years for a smoke alarm; replace a CO alarm by the date printed on it
Signs it is near the end:
- The manufacture date on the back label is about 10 years ago (smoke alarms).
- It chirps even after a new battery.
- False alarms are getting more frequent.
- A CO alarm has reached the date printed on it, or gives its end-of-life signal (these vary by manufacturer, so check the manual).
- Test every alarm monthly by pressing the test button.
- Replace batteries on the schedule in the manual (the clock change is an easy reminder), unless the alarm has a sealed battery.
- Vacuum the vents gently now and then.
- Write the install date on the alarm, and replace smoke alarms after 10 years.
- Keep alarms away from kitchen and bathroom steam where you can, and consider a photoelectric alarm near a kitchen.
- FurnaceFall
The furnace runs but the house stays cold, which is usually a clogged filter, a thermostat setting, or an ignition fault.
- Heat pumpFall
The heat pump runs but the house stays cold, which is usually thermostat settings, a clogged filter, or an iced-over outdoor unit.
- Washer
Water is left in the drum after the cycle, which is usually a clogged pump filter or a kinked drain hose.
- Fridge
The fridge section is warm or warming. The cause depends on whether the freezer is still cold, and the first fix is often free.
- Washer
The drum fills and washes but won't spin, which is usually an unbalanced load, the lid switch, or a drain problem.
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- the front of the alarm, including any lights
- the label on the back with the manufacture date
- where the alarm is mounted (near a kitchen or bathroom?)
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