Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 mygfcxx1 95
6 ahowell 95
7 KnowledgeBase 95
8 skbloom 80
9 Guest_98024861 70
10 Guest_9311297 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 1/26/2015

how ofter do hardwired smoke detectors need replacing and who is the best person for this job

We've got a 15 year-old house with 5 hard wired detectors. A couple have started 'chirping' all of the time and it doesn't go away when I replace the 9 volt batteries.

Do you have the same question? Follow this Question

Voted Best Answer

Probably depends on brand, but I have several over 40 years old that still work fine when tested - both by push button (which only tests the internal electronics and horn) and by testing with spray test gas (which tests the actual detector's ability to detect particles/gas - which you can get at Radio Shack, some auto supply stores, many hardware stores, and lumber yards and home improvement centers - made by CRC and others.

Couple of possibilities - since they are hardwired, especially since relatively new, they might be interconnected in one or more circuits - so if one goes off, one or more other ones do also. Therefore, if any one of those that are interconnected together (which might be in pairs, or maybe in a large circuit with all five) starts chirping due to low battery, all the ones interconnected to it will too. Therefore, you would have to replace the battery in ALL the detectors that are chirping to find the one causing the beeping. And of course, if you don't have a volt-ohm meter or battery tester, it can get real frustrating, because I have found in doing this that about 5% of brand new batteries with expiration dates 5 or more years in the future are low or dead - factory defects. And this is across the 4 large brands - gets really frustrating, so I test all batteries before installing now. New 9V battery should be over 9V (if testing with volt-ohm meter) - usually 9.2-9.4V.

Second possibility - some will beep if the detector gets too dusted up - use canned air (NOT containing propane or butane) to blow out the air slots leading to the detector - or blow out the sheet metal/foil enclosed detector directly if alarm cover comes off, so you can get to it. Hold back a bit when doing this, so you are not spraying extremely subfreezing liquid spray from the can on the electronics and thermal shocking them - usually there is a smalll plastic tube, and you can hold back 3-4 inches and still get a good, fully evaporated jet of air on the target. If you use an air compressor, it has to have microfiltration filter in-line or you will spray oil droplets on the detector, when ruins it because it constantly alarms from then on.

Third possibility - which unfortunately you might only be able to find out is the case by looking at the back or on the slide-out detector/battery module - is several brands now use detectors (fixed or replaceable inserts with battery too) with real long-life batteries, but the modules are programmed to chirp and be replaced after a certain time frame - I have seen 5 and 8 year models recently, maybe others time periods out there too. You cannot replace just the battery - the whole slide-out module with combined long-life battery and detector has to be replaced - planned obsolescence.

A handyman might be able to figure out what is going on, but unless you know one who has proven he is good with electric repairs, better off using an electrician. And be sure he TESTS all he works on before he leaves, to be sure they work.

A few other prior questions with alarm issues can also be found below this answer - on who to get to do repairs or change batteries, interconnected alarms, etc.

Answered 4 years ago by LCD

Related Questions

Terms Of Use
Privacy Policy