Why does my smoke alarm keep beeping?

Smoke alarms beep when there’s a problem usually a low battery, expired sensor, or internal fault. Hardwired units may chirp even if power is on. The sound is a warning that your alarm may not protect you properly until it’s fixed or replaced.

Smoke Alarms Chirping

A smoke alarm that won’t stop beeping is more than just annoying. It’s trying to tell you something.
Whether it’s a high-pitched chirp every 30 seconds or a random warning tone at 2am, beeping means there’s an issue.
And in a lot of homes we visit, it’s the first sign that the smoke alarm isn’t working as it should.

Let’s go through why it’s happening, how to fix it, and when to call in help.

1. First, Know the Difference Between a Beep and an Alarm

A beep (short chirp every 30–60 seconds) is a warning.
A full alarm (continuous sound) means it’s detected smoke or fire.
If you’re hearing the beep and not seeing smoke this guide applies to you.

2. What to Do First

Here’s a quick checklist:

• Replace the battery (if it’s a battery model or hybrid). Use high-quality batteries only.
• Vacuum the unit to remove any dust or insects.
• Press the test button for 5 seconds. It should beep loudly, then stop.
• Check the expiry date—if it’s 10+ years old, it’s due for replacement.
• Look for a fault light—many models flash red for battery issues, or yellow for sensor faults.

Still beeping? It’s time to talk to a licensed electrician. You can book us directly through our Smoke Alarm Services page or call us now on 0489 998 552

3. What Is Causing The Smoke Alarm Beeping

Low battery

Even hardwired alarms have a backup battery. If it’s low, the unit beeps to warn you. This is the most common reason for chirping.

Expired unit

Most smoke alarms last around 10 years. After that, the internal sensor loses reliability, and many alarms will beep to indicate end-of-life. You’ll often find a sticker with an expiry date on the side or back of the unit.

Power issues

In hardwired models, a loose connection, tripped breaker, or poor earthing can trigger a fault beep—even if the green light is on.

Dust or insects

Dust inside the sensing chamber can confuse the alarm. So can a spider or flying insect. In this case, a quick vacuum (gently, with a soft brush head) may stop the beeping.

Humidity or temperature

Steam from showers or extreme heat changes can cause some models to chirp or false-alarm. Avoid installing them near bathrooms or too close to kitchens or where cooking and boiling water is being done..

4. When to Replace the Alarm

Smoke alarms should be replaced if:

• They are more than 10 years old
• The beeping continues after battery replacement
• The alarm fails the test button
• There’s damage, cracks, or water staining on the unit
• You’ve had repeated false alarms or malfunctions

It’s also worth checking if your system is up to current Victorian standards. Most homes should now have hardwired smoke alarms with battery backup in key zones.

You can refer to Fire Rescue Victoria’s smoke alarm page for more safety info.

5. What We Do

When we’re called out to inspect or replace a smoke alarm, we:

• Test the unit and power supply
• Check expiry and connection points
• Clean the sensor and housing
• Replace the battery (if applicable)
• Remove and upgrade units as needed
• Install new alarms with 240V hardwiring and lithium backup batteries
• Ensure alarm placement meets current recommendations

All work is certified with a Certificate of Electrical Safety, and we only use compliant models listed on the Australian Standards register.

FAQs

Do I need an electrician to replace a smoke alarm?

Yes if it’s a 240V hardwired unit.
There are Battery only alarms can be replaced yourself, but for anything connected to mains power, you need a licensed electrician.

How long do smoke alarms last?

Most models last 10 years. After that, the sensor becomes unreliable.

What’s the legal requirement in Victoria?

All homes must have smoke alarms that comply with the Building Code. New builds and major renovations must have hardwired models with backup batteries.

Can I disable the beeping without fixing the issue?

Only temporarily. The unit will continue beeping or fail completely until the cause is resolved.

Final Thoughts

A beeping smoke alarm is your home asking for help. It’s easy to ignore—or pull the battery and hope for quiet—but that alarm might be the only warning you get when something goes wrong.

If your smoke alarm won’t stop beeping, let us fix it properly. We’ll clean, test, or replace what’s needed and make sure your home’s protected.