On the latest version of the dual action valve (from Nov 2014 onwards, identifiable by green LED's) it is actually possible to set the valve so the system is pressurised on startup. Gaspar and I had a mammoth email tennis session middle of last year as more people were using these valves in scale jets which would require at the very least the doors to be pressurised on startup. After discussing the pro's and cons he decided to bite the bullet and make the next batch work slightly differently.
The new valve covers both options - in factory delivered state it works as the old version did i.e. system not pressurised on startup but if you power up after programming then press the button it will switch to pressurised mode when powered up in the future. Best to power off after programming, the switch on again, check actions are correct then power off and power on again. At this point you can press the button to toggle pressurised status.
Last edited by Colin Gontier; 04-12-2015 at 10:13 AM.