While many treadmill repairs can be done at home, some issues require the help of a professional. Here are some signs that it is time to call in a professional: 

1. Electrical Issues: If you notice any electrical issues with your treadmill, such as sparks or smoke, stop using it immediately and call a professional. 

2. Motor Issues: If your motor is making unusual noises or smells, it may be time to call a professional. 

3. Console Issues: If you are experiencing issues with the console, such as inaccurate readings or faulty buttons, contact a professional.