Either you love natural brick, or you don't. There are exceptions, but this brick was brown, speckled, and hideous. One day. left to my own devices, I ventured down the path of no return and painted it ALL. Even though it's a lot of painted brick wall, I've never regretted it. So, how do you successfully paint a brick fireplace wall?
Three in one primer and a latex top coat in your color choice. That's it. Nothing complicated or expensive, just prime and paint. It's been well over ten years and not one single problem. Sometimes it's just too easy.