I got 2 units and the heating stopped working. What part do I need to buy and replace?

Your problem sounds like it could be an issue with how it was installed rather than a part issue. If it truly is a part issue, you can submit a Part Quote Request through our site. A member of our parts department will reach out to you after you submit the form. If this isn't a part issue, we recommend calling in and ask for Tech Support. They can help diagnose the issue and provide solutions.