I have a project for U.S. History and we have to find out what Ben Franklin invented.and i can only find some of them so could u help me plz?!?:)
Yes. Hire an electrician.
Why are you working with the circuit live (hot)? Shut the circuit breaker off!!! Are you hooking up an ADDITIONAL smoke detector, or a REPLACEMENT smoke detector? I'm not going to explain WHY it is happening, because you won't understand. Just remove one wire nut at a time and add/replace the smoke detector. White to whites. Black to blacks. Then turn the power back on. p.s. You don't know much about electricity but you're playing with a live circuit! If you're doing this to use the light from the same circuit, do it in daylight. Or use a flashlight. Or plug in a light to a circuit elsewhere with an extension cord. Shut the circuit breaker off!!!
Congratulations! Your thermostat seems to be functioning properly. Now turn it up and the heater should kick in.
If there is more than one white wire then they used the smoke detector as a tie point. That is not the proper way to do it. The white wires should be twisted together and wire nutted with a single pigtail lead coming from the wire nut to the smoke detector. That way the other circuits will continue to work even when the smoke detector is disconnected. And that is what is required by the National Electric Code.
Something is definitely screwed-up in the wiring, suggest you have a pro check things out.
