Place chicken in the Instant Pot. Add chicken broth, water, chicken bouillon, parsley and bay leaf.
Seal the lid and set to pressure cook for 20 minutes at high pressure.
After cooking, wait 15 minutes before quick releasing the pressure. Be cautious of steam.
Remove chicken and shred.
Add celery, carrots, red pepper, onion, diced tomatoes, and potatoes to the broth. Add more broth to measure 8 cups total.
Seal the lid and set to pressure cook for 5 minutes at high pressure.
After cooking, wait 10 minutes before quick releasing the pressure.
Boil noodles according to package directions.
Mash the soup with a potato masher. Add shredded chicken and noodles. Serve.