Richard,
Thanks for the response. I did a bit more research. The plumbing code makes no mention one way or the other. I found the manufacturer of the straps. They are approved by IAPMO (the code publisher) for use in California and are to be installed per the manufacturers instructions.
I had the company email me the instructions and the are okay without going completely around the heater. Here is the link to the company:
Hubbard Enterprises: Pipe Support Systems.