Leaving regulator charged.

[Rick Inman]

I just went out to my truck to switch out tanks for tomorrow morning's dive, and discovered that I'd left the tank turned on since last night, with reg still attached of course. I've done this a couple of times before.

My question is, is it bad for the regular to leave it pressurized for long periods of time?

Also, in my case, I use an Atomic M1, which has a design in the 2nd stage which I call a reverse poppet, where the rubber valve seat is pushed against the orifice only when the reg is pressurized.

Any thoughts?

 

[MoonWrasse]

Well, when I do this on my Porter Cable pancake compressor, it develops
problems and subsequent leaks from the reg.

However that's a different design, so I'm not sure if it helps answer your question

 

[redacted]

I wouldn't expect any problem. You have engraved both the 1st & 2nd stage seats a bit more, but that "bit is extrememly small. In fact, if you had a more common 2nd stage that didn't have the reverse poppet, you would have actually releived a little pressure from the 2nd stage seat.

I usually leave mine pressurized overnight in a tub to clean them after s/w diving.

 

[Rick Inman]

I wouldn't expect any problem. You have engraved both the 1st & 2nd stage seats a bit more, but that "bit is extrememly small. In fact, if you had a more common 2nd stage that didn't have the reverse poppet, you would have actually releived a little pressure from the 2nd stage seat.

I usually leave mine pressurized overnight in a tub to clean them after s/w diving.

That's what I was thinking. Thanks.

 

[wedivebc]

I wouldn't expect any problem. You have engraved both the 1st & 2nd stage seats a bit more, but that "bit is extrememly small. In fact, if you had a more common 2nd stage that didn't have the reverse poppet, you would have actually releived a little pressure from the 2nd stage seat.

I usually leave mine pressurized overnight in a tub to clean them after s/w diving.

Wouldn't there be less load on the seats under pressure? It seems when the air is off the seat is under full spring pressure. When the air is on the air pressure counteracts some of the spring tension.

 

[redacted]

Wouldn't there be less load on the seats under pressure? It seems when the air is off the seat is under full spring pressure. When the air is on the air pressure counteracts some of the spring tension.

With piston 1st stages, the piston in not in contact with the seat when not under pressure. I'd have to go to the books to verify that the same is true for diaphram 1sts. With the atomic 2nds (and the scubapro g500/s600 & x650) a second balance mechanism allows the seat to pull away from the orifice when not under pressure to reduce seat engraving. But for other 2nds you are right. That is why I store mine with the purge button depressed.

 

[Viscya]

With piston 1st stages, the piston in not in contact with the seat when not under pressure. I'd have to go to the books to verify that the same is true for diaphram 1sts. With the atomic 2nds (and the scubapro g500/s600 & x650) a second balance mechanism allows the seat to pull away from the orifice when not under pressure to reduce seat engraving. But for other 2nds you are right. That is why I store mine with the purge button depressed.

Right, your first stage seat is taking a set. The second stage may be getting some relief depending on the design.

Also, your hoses and o-rings are also stressed by this. I try to purge my regs as soon as I am out of the water. Added stress will only shorten the life of the gear, and the time between overhauls.

 

[stevetim]

Right, your first stage seat is taking a set. The second stage may be getting some relief depending on the design.

Also, your hoses and o-rings are also stressed by this. I try to purge my regs as soon as I am out of the water. Added stress will only shorten the life of the gear, and the time between overhauls.

I kinda had the thinking that expansion and contraction over a period of time is actually what stresses materials out. Kinda like jetliners' air frames have xxx number of takeoff and landing cycles before overhauls is required because of metal fatigue from pressurization/depressurization.

Could someone elaborate my idea a bit?

 

[Charlie99]

I just went out to my truck to switch out tanks for tomorrow morning's dive, and discovered that I'd left the tank turned on since last night, with reg still attached of course. I've done this a couple of times before.

My question is, is it bad for the regular to leave it pressurized for long periods of time?

Also, in my case, I use an Atomic M1, which has a design in the 2nd stage which I call a reverse poppet, where the rubber valve seat is pushed against the orifice only when the reg is pressurized.

Any thoughts?

My first thought was "Good thing he has the jet piston".

My Atomics B1 used to develop IP creep every 80 or 100 hours dive time. After upgrading to the jet piston used on the B2 and M1, the problem never reoccured. I think that leaving the reg charged with a full 3000 or 3500 psi during the 45 minute run out to the dive site was also aggravating the situation, so I have started bleeding the system down to 1000 or 1500psi after assembly to check for slow leaks.

While obviously not the preferred condition due to increased engraving/scoring of the 1st stage seat, leaving your M1 pressurized overnight, particularly with a partially used tank isn't going to do much.

Leaving the 2nd stage pressurized isn't any worse than the normal long term storage condition for regs that don't have the seat relief feature.