9670. One minor problem w/orifices is they are subject to blockage, either partially or totally. The orifice needed for 150#/A @ 8 mph isn't very big. NH3 often carries dry rust flakes that can be a problem for screens & magnets. Normally, you don't see this potential problem because there's at least a 1/4" or 3/8" hole all the way to the ground from the tank. Using a 090 orifice gives you a hole that your ball point pen tip won't go thru. Again, this is just a potential occasional problem, not a 24 hr/day problem.

Orifices are good, but I've found more parts than just the TJ discs are needed....."here" anyway. Perhaps others have successfully added orifices only on NH3?

Also, ambrose1, did you realize your same post appears in every forum in NAT?