Why Is My Carbon Monoxide Alarm Beeping?

By David Tait Reviewed by Cormac Breen

Editorial Manager

If your carbon monoxide alarm is beeping or chirping every 30 to 40 seconds, it may be because the alarm needs to be replaced, the batteries are running low or the alarm itself is malfunctioning. If your alarm is emitting 4 or 5 beeps, every five seconds, it has detected a level of carbon monoxide, and you should immediately turn off any carbon monoxide emitting appliances and leave your home. Carbon monoxide alarms cost between €20 to €100 and are available from most home DIY stores such as Woodies.

How Much Does a Carbon Monoxide Alarm Cost?

Carbon monoxide alarms range in price from €20 to €100 depending on the following factors:

• Brand
• Number of special features
• Whether it is wired or use batteries

Basic alarms with standard features like battery power and a loud alarm sound are typically more affordable, while advanced models with features like interconnectivity, digital displays, and long-life batteries tend to be more expensive.

It's important to note that the cost of the alarm itself is a small investment compared to the potential health risks associated with carbon monoxide poisoning.

Below you will find a table with our three recommendations for the top carbon monoxide alarms available to buy from basic to premium pricing:

Make sure the alarm you choose is:

• Complies with European Standard EN 50291
• Carries the CE mark.
• Is marked with an end of life indicator.
• Is audible and not simply a visual indicator.

Alarms are available from most DIY stores such as Woodies and also at larger supermarkets.

Where Should I Put My Carbon Monoxide Alarm?

Where you place your carbon monoxide alarm is important as you want it to be somewhere close to potentially carbon monoxide producing appliances but also somewhere where you can hear it at night if it goes off.

Our recommendations are:

• In rooms with fossil-fuel burning appliances such as boiler rooms, kitchens etc
• Somewhere close to bedrooms so that alarms can be heard at night.
• If you have a two-storey or more house, consider installing one on every floor of your home.

Try not to place alarms too close to cookers to avoid false alarms and install them 30cm away from the ceiling but avoid placing them too close to the corners.

When in doubt, always refer to the manufacturers' instructions.

My Carbon Monoxide Alarm Is Beeping Every 30 Seconds?

If your carbon monoxide alarm is constantly beeping or 'chirping' (every 30–40 seconds), then it may be a result of the following:

• The end of life has been reached (time to change your detector)
• Low battery (replace the battery)
• Malfunction (reset the unit, and if that doesn’t work, replace it)

You should have previously tested your carbon monoxide alarm and be able to tell the difference between this beeping and the actual alarm going off.

Do not ignore a beeping detector, apart from being an extremely irritating sound, the detector will not respond to carbon monoxide in this condition.

My Carbon Monoxide Is Beeping Every 5 Seconds

If your alarm is emitting 4 or 5 beeps, every five seconds, it has detected a level of carbon monoxide in your home and you should immediately:

1. Open all the doors and windows in the house.
2. Turn off any fossil-fuel-based appliance which could be a source of carbon monoxide.
3. Exit the house.

If anyone is showing symptoms, exit the house immediately. Do not re-enter your house until you have been told it is safe to do so.

Call emergency services and let them know your condition, the condition of those around you, and any other information you may have. They will then send someone to assess you and your house.

What Are the Symptoms of Carbon Monoxide Poisoning?

When in an enclosed area containing anything that might produce carbon monoxide, keep an eye out for the sudden onset of these symptoms, experienced by yourself or other household members:

1. Blurred vision
2. Confusion
3. Dizziness
4. Dull headache
5. Loss of consciousness
6. Nausea/vomiting
7. Shortness of breath
8. Weakness

Many of these symptoms are subtle or not easily attributed to carbon monoxide poisoning, which is why it is also important to have a carbon monoxide alarm installed in your home.

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Where Should I Put a Carbon Monoxide Alarm?

You are most at risk from carbon monoxide while asleep, as you may not notice the symptoms which would normally alert you to the fact that something is wrong.

Therefore, it makes sense to place your carbon monoxide alarm somewhere it will wake you up if you are sleeping.

While placing an alarm near your bedroom is helpful for the reasons we outlined above, you may need several more alarms to take care of safety during the daytime when people are awake and in different areas of the house.

The kitchen and living room tend to be safe bets to place detectors, but realistically any room where there is a potential source of carbon monoxide should have one.

What Is Carbon Monoxide?

Carbon monoxide is a toxic gas which can make you sick or even cause death. It has no smell, taste, or colour, and as such has come to be known as the “silent killer”.

The gas can be found in any Irish home from improper burning of gas, oil in your condensing or oil boiler. The improper burning of wood or coal in a biomass boiler can also produce carbon monoxide.

According to Gas Networks, on average 6 people die in Ireland every year from unintentional carbon monoxide poisoning in their homes, usually caused by faults with installed central heating systems in their homes. This is why it’s so important to have your boiler serviced regularly and to have a carbon monoxide alarm properly installed.

It might also be worth considering replacing your boiler, as the older the boiler becomes, the more likely it is to not function properly. Replacing your boiler with a more modern, efficient model can also help you save on your energy bills.

Where Is Carbon Monoxide Produced?

If there is a lack of oxygen during the combustion process of fossil fuel, then carbon monoxide may be formed instead of carbon dioxide. Items and processes in the home which may produce carbon monoxide include:

• Appliances such as boilers, gas-fired heaters or stoves, and space heaters.
• Generators
• Lawnmowers, chain saws, and pressure washers that are fuel-powered.
• Cars and vehicles.
• Fires (in fireplaces)

To avoid carbon monoxide poisoning, appliances should be well-maintained and kept in good working order, like with regular gas boiler services and bleeding your boiler.

Generators and fuel-powered outside appliances such as lawnmowers should never be turned on inside the house.

Where Else Is Carbon Monoxide Produced?

Vehicles produce carbon monoxide when they are running, so never leave a vehicle idling inside a covered space, e.g. a garage.

The toxic gas can also be released into the car interior if the exhaust pipe becomes blocked, so make sure to check that the exhaust pipe is clear if you’ve been driving in muddy conditions or through the snow.

Fireplaces, chimneys and flues should also be cleaned and checked every year.