I had a plumber run a natural gas line out to my Weber grill. He then installed the natural gas adapter to the Weber grill. There is a shut off valve near where it comes out of the house. And one in the basement which I shut off if I'm not going to be using it for awhile, like over the winter. I can't tell you how much easier it is than schlepping those heavy gas tanks (not to mention running out while grilling something!) and how easy it is to turn it on and off. I simply turn the valve on, then turn the grill knobs to "on" and grill as long as I want. Then when it's time to turn it off, I turn off the knobs and then the valve. If I buy a new gas grill I'll buy one that is designed for natural gas use. Having the natural gas hookup has made grilling as easy as using my gas stove inside. So far as the igniter, my broke early on, but I didn't replace it. I just use one of those red pistol type candle lighters that fit in the lighting hole safely. Whoooshhhh!

Natural gas has a real low delivery pressure most likely there is nothing wrong with the valve or piping. You probably simply have a spider web in your burner orfice. Remove your burner and clean the entire assembly and you will be good to go.

Try blowing it out with a compressor or clearing it with a wire. Spiders build nests on these cavities blocking flow. Ron

The piece would be a stainless steel or brass fitting that is flared on one end and male threaded pipe on the other. You typically see this fitting connecting stainless steel flex gas line to the iron gas pipe. I don't normally see it sold individually - only with a flex gas line. Be sure you use teflon tape on all of your joints (yellow teflon tape for gas) except for the flair fitting. Also be sure you leak test everything with soapy water. I hate to say it, but the better answer is to do this with one hose. Connecting them together like that is borderline bogus.