I was wondering if someone could tell me how to change the battery on a Firex smoke detector? The smoke detectors seem to be wired to the house with a backup battery in case the power goes out.

It's not as simple as just pulling out the old battery and popping in the new one. There's a plastic mold or case(with one red wire, one black wire, and one yellow wire) covering where the battery is held. So, basically I need to somehow remove this before I can get to the battery. Can anyone tell me the safe way to do this?

I'm not trying to get electrocuted here :) Any help would be appreciated.

It's still that simple, that case as you call it, just pops out, the wires are connected together, and will pop off the end, don't worry about it. Put the new one in the same way. A screw driver may have to be used, they get tight after a few years.