Scubapro R195, enabling anti-set causes slow leak?

[novasquid]

This may be a silly question, but I was curious... I have one octo R195 with the anti-set, anti-engraving enabled that allows a slow leak/hiss. I have two sets of G260 and two sets of R195 2nd stage regulators, and this one R195 with anti-set enabled is the only one that does this while connected to a HP119 tank. Each pair of 2nd stages are connected to an MK25, with an IP of around 138-139.

Is this normal, should I get the one R195 regulator looked at, or the other 3 that does not do this?

 

[halocline]

It's tough for me to know exactly what you're describing. The 'anti set' feature on my R190s is engaged by turning and depressing the purge slightly until it catches, meaning the purge is maybe halfway depressed. If you were to hook this regulator to a tank and turn on the air, you'd have a massive free flow, not anything like a 'slight hiss.'

You must be talking about something different, right?

 

[novasquid]

No, that's exactly what I'm talking about. This one R195 regulator will make a slight hissing noise while all the others don't make a sound when they're all set with the anti-set feature and hooked up to a full tank. I wasn't sure if the one that hisses needs to be checked out or the other 3 that do not hiss.

While under pressure, if I try to unset the anti-set feature on them all, they will all free flow.

 

[Fishpie]

I would guess the "anti-set" will relieve the pressure from the seat for storage. Whether that completely removes contact between seat and orifice or just reduces some of the spring pressure would depend on the state of tune of each individual reg......I would suspect that the one that hisses is set to be easier to breathe from and is doing what it is designed to do.
The fact that they FF when you mess with the cover/purge is to be expected if the venturi (VIVA) is in "dive" or +.

 

[LeadTurn_SD]

Turn off the tank valve. Purge one of the regs to bleed off all air pressure. "Unset" the anti-set on all of them. Make sure the purge buttons are moving smoothly, and are in their "normal" position, and are not sticking.

Turn the air back on.

Do any of them leak now?

I'm not 100% familiar with your exact regs, but if I generally understand what you are describing from other regs that I've seen, it is a "feature" designed to prolong the life of the 2nd stage soft seat by locking the purge button in a slightly "depressed" position. This causes the demand lever to be depressed slightly, which in turn slightly separates the mating surfaces of the 2nd stage valve, which helps prolong the life of the soft seat.... so yes, I'd certainly expect at the very least a "hiss" of air escaping past the 2nd stage soft seat since the demand lever is depressed slightly.... and most well-tuned 2nd stages that have a strong venturi effect will freeflow dramatically on the surface if you sharply depress the purge button with the reg out of your mouth (i.e., without backpressure).

Best wishes.

 

[novasquid]

The fact that they FF when you mess with the cover/purge is to be expected if the venturi (VIVA) is in "dive" or +.

i should clarify that "free flow" was the wrong words to use. when i push the cover to unset the anti-set feature, they flow air as one would expect but are NOT in a free-flow. sorry for the confusion.

Turn off the tank valve. Purge one of the regs to bleed off all air pressure. "Unset" the anti-set on all of them. Make sure the purge buttons are moving smoothly, and are in their "normal" position, and are not sticking.

Turn the air back on.

Do any of them leak now?

NO, none of them flow air when the anti-set is not enabled. they all breathe fine with the anti-set unset, so i guess it's just a matter of fine tuning that's causing the one R195 to behave a little differently than the other three 2nd stages.

time to go read the "scuba regulator maintenance and repair" book!

 

[LeadTurn_SD]

i should clarify that "free flow" was the wrong words to use. when i push the cover to unset the anti-set feature, they flow air as one would expect but are NOT in a free-flow. sorry for the confusion.




NO, none of them flow air when the anti-set is not enabled. they all breathe fine with the anti-set unset, so i guess it's just a matter of fine tuning that's causing the one R195 to behave a little differently than the other three 2nd stages.

time to go read the "scuba regulator maintenance and repair" book!

I think you've got it figured out. Well done!

Doing some reading on the topic of regulator function and repair is very worthwhile. Removing some of the "mystery" that surrounds regulator function and servicing will increase both your comfort in the water and your ability to "diagnose" small gear issues at an early stage.

Best wishes.

 

[redacted]

It seems to me that they should all leak quite a bit when the anti-set feature is engaged. If not, then the anti-set feature is not working.

 

[halocline]

It sounds like the lever is really loose on a couple of your 2nd stages. If you pressurize the regs without the anti-set feature engaged, and then shake the 2nd stages, do you hear a rattle?

Adjusted correctly, the lever should just about contact the diaphragm when the reg is pressurized. I suspect yours don't on the two regs, and if there's a lot of play there, the purge button won't be nearly as responsive. This directly impacts how well the reg breathes. So I'd get it checked out.

I don't know what to say about the G260....I've never even seen one. I have had a few G250s of various generations, I don't remember any of them having this anti set feature. It makes sense that they would include it, it's more-or-less the same cover/purge button as the R190.

Unless they've really changed the anti set design, it should flow like a banshee if it's engaged and adjusted properly.