Subdriver Propel Charging how long?

[Slats]

Hi David,
just assembled my 3.5 Subdriver and am doing some preliminary bench tests etc to assure proper working of all electronics and my fail safe. The gas saver is working fine, but I do have a question re the charging of the unit.

Yes I am pre chilling down the unit. I am wondering how long I should be holding the bottle down on the charge valve for to fully charge the gas tank? I.e. Held it down there for twenty seconds and am thinking was this too much / too little?
I cycled on the bench charges with the radio and fail safe by holding up the float of the gas saver and counted 12 good size blows, followed by at least another 12 smaller type blows (smaller in the sense that you could here the gas and smell it, but these lacked the big woosh of gas of the larger ones).
Would appreciate your advice on what indications there should be when the gas tank is full of propel and about how long this takes?

(Of interest also was I noticed that when there was vertually no blows left, there was still via venting the charge value a good woosh of propel liquid still in the tank?!)

many thanks

John