I have two lights in one room that are turned on with a dimmer switch in that room. I also have a light in the kitchen that is turned on with a dimmer switch in that room. My problem is the dimmer switch in the kitchen also turns on and dims the lights in the other room. The other room was an add on and wired to the existing wiring from the kitchen. How can I make the dimmer in the kitchen work only for the kitchen, while the dimmer in the other room works only those two lights?
Sounds as though the feed for your other room is simply connected to the wrong side of the kitchen dimmer switch. The kitchen dimmer is in series with the other room dimmer. This was presumably deliberate at the time.
Move the connections that feed the other room to the other side of the kitchen dimmer. This will take the kitchen dimmer out of the other room's circuit.