Flex connectors cannot be spliced per their listing. They also cannot be reused per their listing. All flex connectors except dryers and ranges are limited to 3ft; hose two appliances are allowed 6ft.

Get a copy of the IRC Commentary instead of the NFGC unless you know NFPA 54 is still being used in your area. Most of the country is now under the IRC and thus the IFGC.

Sediment traps are required by code everywhere, regardless whether or not your inspectors call for them.

I don't know of any jurisdictions that don't allow flex connectors if properly installed.

Bob

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