Items you will need
Portable black light
Commercial odor remover
Whether your dog is just learning to go outside or it is just an isolated incident, dog accidents happen. Dried urine stains are much harder to remove than fresh urine stains because they have had time to set into the fiber of the carpet. Dried urine stains are much more likely to cause difficult to remove odors in your carpet. Some large stains with lots of urine can even sink through your carpet pad and cause you to replace an entire room of carpet.
Find the dog urine stain. Dried dog urine can be hard to find in carpet. Check the areas that your dog has urinated before because dogs like to visit the same spots. You may also try a portable black light to find stains that cannot be seen easily with normal eyesight.
Clean the urine stain using an odor neutralizer agent. Basic baking soda works well. Spray water on the dried dog urine stain until the area is slightly damp and then sprinkle baking soda over the area. Let it air dry and then vacuum the powder up.
Mix a white vinegar and water solution as an alternative method of removing urine odors. The mixture should have two parts water to every part white vinegar. Spray enough solution on the area to dampen it. Gently blot dry with a paper towel.
Purchase a commercial odor neutralizer. This too should be sprayed over the stained area until slightly damp and then blotted dry. Remember to always read the instruction of any commercial odor neutralizer before you use it because directions can vary depending on the product brand.
Check the carpet after you have cleaned the stain with an odor neutralizer. If there was a lot of urine, it may have seeped through the carpet into the carpet pad beneath. Lift up the carpet to check for the telltale stains beneath the carpet. Consider steam cleaning your carpets or having them professional cleaned to remove further urine odors.
To prevent the dog from coming back and using the area again, spray a commercial spray designed to keep dogs from being attracted to the area. You can also mix a little chili powder with water and spray it over the area, too.
If after all of the above steps the urine smell is still in your carpet, you may have to just replace it. This is especially true if there are lots of stains or a few very large stains in one area.
Always spot test any cleaning substance in a non-visible area before using it on your carpet. This way you can tell if the substance will discolor your carpet before you use it large amounts.
If your dog has been housetrained and suddenly starts having accidents in the house, it may be a medical problem. See your veterinarian if you think your dog is having problems holding his bladder.