The CA approved Next Century meters (both cold and hot) are calibrated to a more exacting standard. The AWWA (American Water Works Assoc) standard allows for 3% variance on low flow and 1.5% on medium and high flow. In order to be a CA approved meter, they are calibrated to 0.1% standard in order to maximize the pass rate in CA. This requires a lot more time and testing at the factory which is why they are different from the standard meters.
When purchasing the regular Next Century meters, you are getting a AWWA compliant, NSF certified, and NTEP certified meter. It is possible that this meter, even though it meets all of these tight standards, can be tested by weights and measures in California and not pass. Many manufacturers have stopped honoring warranties in this situation because they have found faulty testing procedures and equipment as well as untrained staff in weights and measures resulting in the failure. So, they have offered this meter that is even more dialed in to accuracy in order to create a buffer and result in passing the weights and measures tests. It goes above and beyond the traditional excepted standards.
Still Unsure?
If you have any doubts or questions about selecting the correct pulse output for your water meter, don't hesitate to reach out to our customer support team at 855-871-6091 for assistance.