Electrical Wiring in the Home/blackened smoke detectors


QUESTION: We just purchased a short sale home built in 2002 that has 7 hardwired Kidde smoke alarms with battery backup.  Most had been removed by the owner and laying on the floors as they were "chirping" and he didn't want to pay for a new battery!   Anyway, the base plate of all the detectors have blackened areas as if black smoke/soot came from the detectors themselves.  It wipes off so the base plate was not scorched and the wiring inside the boxes looks ok (no area that insulation looks like it got hot. There is no evidence of soot on the ceiling around the detectors just the blackened areas on the base plate.  As a FYI the detectors hook to the wiring via Kiddes three prong adapter   There is electricity going to the detectors as when I plugged one in that didn't have a battery in it the detector started chirping.
I didn't think its any big but wanted to see if you had seen this

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QUESTION: Is the blackened area on the base of the smoke alarms something we should be concerned about as a fire hazard?  The black wipes off the base, so it is not scorched.  There is electricity going to the detectors.

I don't know how black "blackened" is. If they are all alike it is probably from the normal function of the detectors in the environment of that building.
At ten years old it is time to replace the smokes anyway. Remember to install a combination smoke/CO detector as part of your replacement process.
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Electrical Wiring in the Home

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Robert Wilber


Licensed Philadelphia electrician serving Delaware, Chester, Montgomery and Philadelphia County in Pennsylvania. I install and repair residential, commercial and industrial wiring and lighting. Troubleshooting and repair of problems that stump other people is my favorite. I am willing to help people figure out why things don`t work. I understand motor controls, transformers and machine wiring. I do not teach basics to novices or do free design work.


Experience in the area I have 44 years experience in residential, commercial and industrial electrical construction and repair, 480 volts and below. This is not to be confused with one week repeated two thousand times.

44 years experience in residential, commercial and industrial electrical construction and repair

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