Smoke Alarm Beeping? When to Fix It and When to Replace It

A beeping smoke alarm is the alarm asking for something. DFES puts it plainly: if your smoke alarm beeps or chirps, it needs maintenance or replacement, so do not ignore it. [A] The trick is working out which, and that depends on what kind of alarm it is.

What kind of smoke alarm do you have?

• Battery alarm with a replaceable 9-volt battery. Common in older homes and sheds.
• Battery alarm with a sealed 10-year lithium battery. The battery cannot be changed. When it runs out, the alarm is replaced.
• Hardwired (mains-powered) alarm. Wired into the house, with a backup battery inside. This is what WA requires in homes being sold or rented. [B]

Why is my smoke alarm beeping?

• Low battery. The most common reason. A 9-volt battery should be replaced every year. [A]
• Dust. Dust and cobwebs can make an alarm beep. DFES suggests cleaning it first with a soft brush on a vacuum cleaner, and wiping around it without spraying anything inside. [A]
• A power cut. A hardwired alarm runs on its backup battery while the power is off, then recharges. The beeping should stop within about two hours. [A]
• End of life. A 10-year lithium alarm beeping about once a minute with the red light flashing has run out, and needs replacing. [A]
• A fault. If it keeps beeping after a new battery and a clean, DFES says it is likely faulty or at the end of its life. [A]

Is it time to replace the smoke alarm?

Look for the date printed on the alarm. DFES says all smoke alarms must be replaced every 10 years, because their sensitivity drops over time and they become unreliable. [A] So an alarm that is more than 10 years old needs replacing even if it is not beeping.

If one alarm in the house has reached its date, check the others. Alarms fitted at the same time reach their date at the same time.

Hardwired smoke alarm beeping: what you can and cannot do

You can press the test or hush button, clean the alarm, and change a backup battery if the manufacturer's instructions say it is user-replaceable. Mains-powered alarms do have backup batteries that may need replacing. [A]

What you cannot do is take the alarm off its wiring and fit a new one. In WA, only a licensed electrical contractor can connect or disconnect a mains-powered smoke alarm. [B] If a hardwired alarm is faulty or past its date, the replacement is an electrician's job.

Selling or renting: the 10-year rule

Before a WA home is sold, rented or hired, its smoke alarms must be in working order, permanently connected to mains power, and no more than 10 years old. Where there is more than one alarm, they must be interconnected, unless the home was built on a building permit applied for before 1 May 2015. [B]

In a rental, the landlord is responsible for keeping the alarms compliant. The tenant only changes a 9-volt battery where the alarm is easy to reach, and should test the alarms every month. [C] I replace smoke alarms for landlords and property managers and can arrange access with the tenants directly. The full rules are in WA smoke alarm rules for selling or leasing, and the paperwork for a sale in the electrical safety certificate when selling.

What I fit

When I replace smoke alarms, I fit mains-powered photoelectric alarms, which is what DFES recommends because they are better at detecting smouldering fires. [A] Where more than one alarm is needed, they are interconnected so they all sound together. For what is involved and the service itself, see smoke alarm installation in Perth. If you are selling, the alarms and the RCDs are usually checked together in a pre-sale electrical inspection.

Common questions

Sources

1. Department of Fire and Emergency Services (DFES), Smoke alarms. www.dfes.wa.gov.au
2. Building and Energy, Smoke alarm laws for homes being sold, rented and hired. www.wa.gov.au
3. Consumer Protection WA, Rental home safety. www.consumerprotection.wa.gov.au