Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally until tender yet firm to the bite, 8 to 10 minutes. Drain well.
Heat a large skillet over medium-high heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease. Add water and taco seasoning mix and simmer until thickened, about 5 minutes.
Stir refried beans, Cheddar cheese, and green chiles into ground beef; cook and stir until cheese is melted and mixture is smooth, about 5 minutes. Fill shells with beef mixture.
Combine tomato sauce and picante sauce in a saucepan over medium-low heat; cook and stir until heated through, 5 to 7 minutes. Spread 1/2 cup sauce in the bottom of a 9x13-inch baking dish.
Arrange stuffed shells side-by-side in the baking dish and top with remaining sauce. Cover dish with aluminum foil.
Bake in the preheated oven for 40 minutes. Let stand for 5 minutes before serving.