Charts Module not working for one site - No messages in the log
As the Charts maintainer, I am happy to help. My first recommendation is to update to the latest version of Charts (beta1). This has improved handling of fields within Views and a new default in place for Charts Attachments that prevents some issues that users have faced previously. The next thing, and what I think is most likely, is that the libraries did not install properly. Please try disaggregating your JS (from the Admin > Config > Development > Performance page) and then on the page where the chart should be displaying, try inspecting the code and looking for the library's .js file (e.g. highcharts.js). If you're using Chrome, the console tab may tell you something about what is happening.

This also seems silly to say, but be sure your View has results, that it has a field for a title and a field for data, and that those are set in the format settings. This should help for most issues you would experience, but if you are still having trouble please add more information to this post so that your issue can be better diagnosed. Good luck!