Pop Upon Removing Regulator

[divinh]

Has anyone experienced a "pop" upon removing a regulator from the tank?

- Regulator has DIN to Yoke adapter
- Tank off
- Second stages depressurized
- Inflator depressurized

Slight difficulty in turning the knob on the Yoke adapter, then "pop".

I've used the regulator on multiple dives since without issue, but was just wondering what might be the cause of this.

 

[Storker]

My guess is that you didn't depressurize the LP system properly. It's happened to me too (DIN valve and reg) when I didn't hold the purge button a couple of seconds more than I originally thought necessary.

And if you purge the 2nd stage properly, there should not be any need to also depressurize the inflator. It's connected to the same LP system as your 2nd stages

 

[BoltSnap]

System was still pressurized.

 

[Dirty-Dog]

Can't pop if it's depressurized...

 

[Brian G]

If you close the tank valve then give one of the regulators a quick purge, there is still residual air in the high pressure section of the first stage/hp hose. Holding the second stage purge button for a 2 or 3 more seconds (you can usually hear a hiss of air coming out if it's quiet) will allow the high pressure air to completely escape.

 

[Colliam7]

Agree with others - there was residual pressure. Try not only purging both second stages, but inhaling from one as well

 

[shurite7]

Agree with the above. I teach my students to hold the purge button down while unscrewing the yoke. After a couple of turns they can set the second stage down. The hole in the HP hose is very tiny which restricts air movement. If you don't hold the purge button down long enough not all of the gas will escape.

 

[divinh]

Thanks all.

I suspected that I didn't depressurize everything. My usual procedure is to turn off the air, purge one of the second stages, the inflator and check the SPG for the needle to go to zero. I think all of that was done and there was still the "pop", which led me to ask if there was something else going on. It's the first time I've experienced it.

I'll make sure to spend a few more seconds or purge while unscrewing the regulator.

 

[soggybadger]

Thanks all.

I suspected that I didn't depressurize everything. My usual procedure is to turn off the air, purge one of the second stages, the inflator and check the SPG for the needle to go to zero. I think all of that was done and there was still the "pop", which led me to ask if there was something else going on. It's the first time I've experienced it.

I'll make sure to spend a few more seconds or purge while unscrewing the regulator.

Now check the o ring on the tank valve isn't knackered otherwise you may get a little surprise next time you use it. I speak from experience on this one.

 

[boulderjohn]

I suspected that I didn't depressurize everything. My usual procedure is to turn off the air, purge one of the second stages, the inflator and check the SPG for the needle to go to zero.

You really only need to purge the second stage until it is truly done. No need to do the rest.