We have two engines with the computer controlled pump. A 2004 E-One with a Hale pump and a 2008 Pierce with a Waterous pump. Is there any way to gate down individual lines? I have tried on both, set at RPM and pressure modes and whenever I gate one back the computer resets it to pump pressure. This is aggravating when you need to reduce pressure on one line. Am I missing something? I don't know w…