I came across a question about pet stains on hardwood. The following comment and question was asked.
"I left my dogs alone for a couple days and they peed EVERYWHERE. The hardwood floor is dark in some spots and after mopping it still smells! Does anyone know a way I can fix this without tearing up the floors????"
In answer to this the following was written.
"From your description it sounds like the urine has soaked into the hardwood. I have hardwood floors that are sealed well with a quality sealer. When our dog was a puppy she would pee on them often. We were lucky because the urine beaded up and we were able to wipe it up and remove it. Eventually I know it would have found its way into the hardwood, had it been in greater volume or left to sit for too long of a time. There are different types of products available that will eliminate the smell but they have to come in contact with the urine residue. This means you have to soak them into the hardwood to reach the urine. Some of these products will also remove the pet stains. One of the challenges with wood is that the moisture from the urine or the chemicals can warp the hardwood and cause additional damage. It might be worth a try though. If you can’t get the smell and stain out to your satisfaction with these products then the next step is to sand it down removing the stain and odor and refinish the hardwood. If this does not work then you are to the replace the floor stage which is usually the most expensive."