Remove the corned beef brisket from the packaging and rinse thoroughly under cold running water. Place it on a plate, and pat dry with a paper towel. Set aside.
Put your carrots and the diced potatoes in the bottom of your slow cooker. Place the corned beef brisket on top of the vegetables with the fat side up.
Sprinkle the top of the corned beef with the ground pepper, garlic powder, and celery salt.
Pour the beer into the slow cooker, covering the veggies and meat.
Cover and cook on low for 8-10 hours or on high for 6 hours.
One hour before the crock pot finishes, add the sauerkraut. Gently place it in the slow cooker around the corned beef and submerge in the broth/liquid. Cook for the remaining time.
Remove the corned beef to a plate, slice, and enjoy with the veggies and kraut from the slow cooker.