I am slowly but surely replacing all the old switches in the house as many do. I am new to this and could use some advice. The switch I pulled out has two black and one red wire. I am looking for help how to wire correctly or if I have the right replacement switch or if I need something else.
The old switch was what is called a 3 way switch. Means there is another switch somewhere that switches the same light.
You need a 3 way switch, which you can identify by having 3 screws on it (not counting the ground wire)
The new one you have is just a normal 2 ways switch (2 screws).
Once you have it just use the photo to conect it correctly (duplicate the wiring)
3 observation, you have some humidity inside the wall, find out why. Second they used what is called back stab for the wires, it is recommended to use the screws. Third: we are bit concerned for your safety working with electricity, always double check the power is off, do not trust the breaker (it might be the wrong one) use an instrument to check.
As for hunting for the other 3 way switch, many of us discover it by accident or after long time. Start with what is this switch switching, then use logic where would be the other switch for that light. You might need two people, one watching the light and the other going around and activating all the switches.
