Managed to find the MOST cool thread on TRF ever
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Now on to some answers:
- The crown was being sucked back into the watch as the internal pressure was less than the external. This shows that the watch is tight (water/air proof) and it is perfectly normal.
- No matter how much gas (be it He, O2, N etc...) is then allowed inside the watch (by say unscrewing the crown) it will be expelled from the HRV (which does NOT expel only Helium, but any gas that happens to be inside the watch).
- Once the internal pressure inside the case is higher than the external (say during deco) by an appreciable degree, the valve will be deployed by this same differential pressure and all will be perfectly fine again.
I am just a common diver so have no use for HRVs etc. Still I'm sure that I'd reach for my 7c46 powered Seiko if I ever were to do Sat diving
..but I am sure the DSSD is quite capable
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Well done again aquanaut
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