JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I checked your website and the form does not load sometimes. The form uses a script to calculate the height, seems like this script is failing sometimes, it could be due to a conflict with some scripts in your website or something else. I would suggest you to use the iFrame method instead, you wil avoid this conflict and if you want, you can also set the height by default, take a look on this guide to get the iFrame code: http://www.jotform.com/help/148-Getting-the-Form-iFrame-Code.
Do let us know if it works.