Troubleshooting smoke detectors that beep

How to fix beeping smoke alarms

One of the most common problems customers ask for help with smoke alarms is intermittent beeping noises. So if your detector is driving you mad because it keeps beeping; (which sounds like a bird chirping) here are some things you can check:

  • Mains failure – your detector has lost its power supply. Most models display a green light when all is well.

Some smoke alarms have their own circuit from the consumer unit. So if the power was removed you wouldn’t know straight away because the battery back-up would step in. Some smoke detectors are wired in with the lighting circuit so in the event of power failure you would likely know straight away as the lights wouldn’t work either.

Other reasons smoke detectors beep

  • A faulty battery. Some models have replaceable batteries. Manufacturers usually recommend they are replaced every twelve months. If your detector has replaceable batteries; you can replace them and see if the beeping noise stops. Some models have sealed, lithuim batteries which cannot be replaced. They charge from the mains power and more reliable than the alkaline models.
  • Cleaning is necessary. Regular cleaning will help your detector work as intended and reduce false alarms. With the power switched off; use the thin attachment and vacuum the vents. You can wipe the cover with a damp cloth. Don’t forget to switch the mains back on and test the unit.
  • Hush (or silence) feature is active. In the event of a false alarm; users can silence the alarm whilst the room is cleared (usually for around ten minutes).
  • The right alarm. Are you sure the beeping is coming from the detector you are checking? Sound travels so if possible get others to help by standing close to the detectors on a step ladder to ensure you have found the one that is beeping.
  • Remove it. If the detector head has been removed along with the battery and you can still hear beeping then its somewhere else. The AICO models i install do not have sounders inside the base unit fixed to the ceiling.
  • Faulty. Smoke alarms can develop faults. Inside the warranty period they can be repaired or replaced by the manufacturer. Outside this time they will need to be replaced.
  • Expired. Most are made to last ten years. Has your detector expired?

I was called out one morning by a customer in the City Centre who installed his own smoke alarms the previous evening. He took the supply from nearby light fixtures which is a pretty standard after-market method of installation. Everything was fine initially, but he couldn’t work out why they started chirping not long after he went to bed. In older parts of Cardiff the way lights used to be wired often meant the light fitting only had what electricians refer to as “the switched live”. That is the wire that is live when the switch for the light is in the on position. Smoke alarms need a constant power supply to work properly. The detector was working correctly. It was beeping because the mains supply has been lost and needed new wiring to get working correctly. The customer hired me to install Aico detectors and the necessary wiring in his city centre apartment and all was well.

How can i identify what alarm has detected when i have four?

If your alarms are inter-connected; the alarm detecting will have a red light flashing rapidly. Press the silence button for a few seconds on this one and it should silence all of them. If your detectors are stand-alone (so one does not trigger the other) – then it will be the detector making all the noise!

Are your detectors beeping after electrical work has been carried out?

If you have a chirping alarm after the power was switched off its likely the detector(s) need to be replaced due to their age, a fault – or both. The lithium models will beep whilst recharging, however they should keep the detector powered for around 72 hours when working correctly. So if the power has only been off for a few hours whilst the fuse board has been replaced for example it shouldn’t cause any problems with a healthy alarm.

How you can stop false alarms when cooking

Ensure the cooking area is well ventilated. The most common reason for false alarms whilst cooking is due to the wrong type being fitted. Heat detectors are the best choice for kitchens. They look for a sudden rise in temperature and less likely to alarm when the toast gets burnt. New detectors come shipped with covers which can be used when cooking. Just remember to remove them afterwards!

Smoke alarms beeps that beep when battery is installed

On non-mains detectors like the Aico Ei100 series it is normal for the alarm to sound for 2-3 seconds.