In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Tim, A previous post got me curious so I went to Navian's website to investigate. Here is their claim:
Better Adaptability to Gas Systems
The Negative Pressure Gas Valve and Fan with Dual Venturi operation allows for better adaptability to low gas pressure applications. This industry leading technology makes it possible for the NPE to be installed with 1/2" Gas Lines up to 24'.
Easy residential tank replacements.
Maybe if the unit was mounted a foot away from the meter and had no fittings.
Or am I missing something about their "Negative Pressure Gas Valve and Fan with Dual Venturi" that defies everything that I have ever learned about sizing gas piping.