Quote:
| Originally Posted by [b Quote[/b] (NeilB @ April 06 2004,08:14)]Aint regs meant to 'fail safe' these days? For the second stage to have no air but the first stage still to be presurised then there is a failure somewhere in the first stage valve (doh!). My best guess whould be the pressure spring on the back of the first stage (behind adjustment screw). If this broke there would be no back pressure to open the valve to let the air into the second stage.....course depends on what type of regs you have.
It does this on a Mares....I know because I did it this weekend diagnosing my leaky first stage valve seat. In my case though I had taken the spring out and had hoped the air pressure would blow the seal out. It didn't. All it did was to pressurise my first stage. To purge I had to press the back of the valve. Oh well....repair kits on their way, just have to wait a few days. |
IIRC, it is a bit of a white lie saying all regs are failsafe.
I believe the real truth is that most 2nd stages are fail safe and designed to fail open. However some 1st stages can fail close.
Actually giving it further consideration, the phrase "Failsafe" is actually complete tosh. How safe would you feel if your 2nd stage went completely nipples skyward and free flowed at 30m!.
Daz
__________________
Underwater rock juggler extraordinaire
Breathe in, breathe out. Repeat as necessary