Do you have wired in smoke detectors but are experiencing a chirping sound coming from one of them? Have you tried changing the battery but it still chirps? Smoke detectors have an expiration date which is about 7-10 years. If your smoke detector has been around awhile, it might need to be replaced. Replacing a wired smoke detector will cost you about $50.00 at most local hardware stores, or you can order one online. However, if the smoke detector chirping is driving you a little nuts, you may want to make a trip to the hardware store soon.
Replacing the wired smoke detector is not hard or complicated, it basically just unplugs from the base which is affixed to your ceiling.
You can take the whole thing with you to the store and get the same type. Then just plug it back in, make sure there is a fresh battery in it, and you should be good to go.
If you have done these steps and you are still experiencing problems, give Peter Needham a call, there may be problems with your wiring which requires a licensed professional.