Place the carrots in a saucepan with enough lightly salted water to cover. Bring to a boil, and cook until almost done, about 5 minutes depending on how thick you slice them. Drain, and transfer to a large bowl. Add the bell pepper and onion to the bowl with the carrots.

While the carrots are cooking, combine the vinegar, oil, tomato soup and sugar in a saucepan. Bring to a boil, and cook for 1 minute. Pour the hot dressing over the vegetables. Serve immediately, or store in the refrigerator in a covered container and serve within 1 week.