Water Heater Question

Ok that's what I thought. It did not seem right to me that it sat that far back from the main tube. But since there was not an old one on there I had nothing to compare with. And letting that gas build up in that chamber was not something I wanted to try. So I will slot the hole and slide it in farther and try that. It does have an igniter but that is not working. When I turn on the igniter switch I can hear the board making a noise but there is no spark. So for now I am using the long grill lighter to light the pilot. Thank You for your help & I will let you know how it goes!
Rob