I would add that at least on particular brand sold at the Home Depot, doesnt want the genset placed under a deck. This brand comes with a 25' whip from the transfer switch, which is then mated to the liquidtight whip from the genset. I try to place it within that 25' radius, because adding to the whip alters the system, and invalidates the warranty.
I don't have NG here, so we run all the gas gensets on LPG. The gas company requires a min. distance of 10' from the tank, not sure about NG though.
The static pressure required for the newer generation is 10"-12" of water column pressure. The older ones run on 11"-14"W.C. As mentioned earlier, volume is a huge deal, as gas companies seen to unersize the pipe even with the manufacturs instructions right in there face. Min. size is 3/4" pipe up to about 15', depending on 90's which add 2.5' to the length of the run. Also temperature affects the volume tremendously, at least on the LP side. These generators are tested at the factory on NG.
If you dont have the manual, go to
www.guardiangenerators.com and you will find all the answers to installation.
