Reasons Your Smoke Alarm Chirps and Goes Off Randomly

For many people that own smoke alarms in their home, these devices are a lifesaver. But if they start chirping in the background, they can also be quite annoying - especially when it’s a false alarm. This can often occur any time of the day and give the user an uncomfortable panic that can be triggering. 

Waking up in the middle of the night to hear a nuisance alarm will get annoying - especially if you need to press the reset button several times.

There are several reasons why there could be a false alarm.

In this article, we will discuss a couple of those in the hope you can reduce smoke detector false alarms. If people hear a detector going off randomly, they might not take it seriously should there be an actual emergency.

The fireplace could be dirty 

If it's winter where you live and use a fireplace with a chimney, then there's a chance that you might get a false chirping from the alarm while you are asleep. Even though fireplaces are designed to facilitate the removal of smoke out of the house, they can sometimes become clogged up.

By this, I mean that they will be closed or clogged up, which means that smoke begins to accumulate in the chimney. It is quite possible that while you were using the fireplace, the smoke alarm may not be off; however, when you leave it on and go to bed, the accumulated smoke can easily be detected and cause the notice to begin ringing. 

This does not necessarily mean that your alarm system is faulty or is malfunctioning but instead is something that is a good sign. You must clean your chimney at least once a year to ensure that there is not a large amount of soot, clear combustion particles that might have stuck to the walls i.e. stop a build up of smoke particles that will prevent future smoke from exiting the chimney. The process of cleaning a vent is not necessarily tricky but will often require a professional to come in and do the job. 

The quickest fix to this is to get a dust cover or a fireplace guard.

Steam Build-up

It might not be considered steam, although the heat and density that is created by steam can begin to trigger the detection system in your household. This is because detectors are often not only detecting smoke but heat i.e. they are photoelectric smoke alarms too. 

If you have one in your kitchen and you are preparing some dinner, the steam may begin to accumulate within the kitchen windows. There is a good chance that the alarm will go off and it’s more of a sign that it works well.

It is just important that when you install a one in the kitchen, you are aware of this. It is easily resolvable by merely opening a window and releasing some of the moisture particles being caused by the steam. Areas such as the bathroom are damp environments and therefore placing a detector in such a room often is unnecessary and will only cause future false alarms.  

Powerful Chemicals

The smoke alarm in your house can easily detect chemicals that come with a powerful and intimate smell. This is a slight defect but also one that has been installed to protect you from harmful gases. That is the main point of a detector. 

If you have recently painted a room that has a smoke detector in it, then you can expect that for the next couple of days, they may be quite a few false alarms coming from the smoke detector. This is because a lot of these gases that come from powerful chemicals are, in fact, explosive. Therefore the sensor has the facilities available to spot them when they arise. Ensure that freshly painted bedrooms are well ventilated to prevent this. 

Poor Alarm Maintenance 

Keep the alarm clean and free from grime.

This is one of the more obvious and literal options on the list one must consider. It would help if you made a habit of always getting your them serviced to prevent it from breaking down and providing you with false alarms. Poor alarm maintenance can come in several different forms, including low batteries and the detectors being clogged up by smoke. 

These devices will need a professional to go into the household and take it down to clean it properly. Once it is clean, it is unlikely to provide you with any false alarms when you begin to use it. It will also detect different gases more accurately, keeping you and your family safe from harmful substances. 

There is also a good chance that your detection unit has been around for a good number of years. This is especially true if you bought it with your house already installed. Usually, people suggest that you should not have standalone detection systems that are older than ten years because it will have minimal accuracy. First port of call should be to check the alarm batteries if you’ve bought a new house.

If you have an interlinked smoke alarm system (wired or otherwise) and if there are regular power interruptions and it isn’t something local to the area, then check if a fuse has gone in your consumer unit. It could be that a circuit breaker is simply causing this.

Think about installing a backup battery if your hardwired smoke alarms system gets too many power cuts due to a local issue in the area.

Could it be that a cooking appliance isn’t getting enough of a power supply? Or maybe the electrical hot shower unit needs a stronger feed? Could this lack of electrical current be causing power interruptions?

The smell of burnt food 

The smell of burnt food lingering within your house can affect the fire alarm on the ceiling. This is because burnt food can produce a smoky aroma, triggering the ionization smoke detectors i.e. this is what they are designed to detect.

In this scenario, if you are cooking food and then you finish up and go to bed, then the detection system might immediately pick up on the smell of smoke particles. To prevent something like this from happening, you must ensure that you ventilate the kitchen well during and after cooking something. We always recommend installing an extractor fan that has at least a 20 minute overrun capability.


In conclusion, there are several reasons why smoke alarms can begin to give off false signals. The main ones to look out for are maintenance issues because this is one of the most prevalent ones. 

Some people go years without having any servicing and then begin to act surprised when it malfunctions. Some people have had theirs installed for years and have not changed them, so they get false results. To avoid nuisance alarms in many cases, what you need to do best is to ventilate the house.