Who should use a CCR?

[RainPilot]

Depends on the unit. There is no real obsolescence in CCR, there is more of a change in tech leading to people buying new units but the existing units still work. Like cars to a certain extent.

 

[tbone1004]

I always wanted to do CCR diving and plan to take it up soon! Since CCRs require quite a large initial investment, I was wondering how long does the equipment last? As in... if I were to invest in a particular unit, how many years will I be able to use it before it becomes obsolete or discontinued? How many hours before a major overhaul?

there are still original inspirations that are doing quite well in the field. 20+ years later. The electronics are considered obsolete, but you can always run in mCCR mode or convert to newer electronics
O2ptimas are right around a decade old and there are still many originals in the field. Most have been converted to the new DiveCAN from Shearwater, but the unit itself is still quite old.
You still see gen1 megs from time to time, though their support will be ending here shortly on the electronics front.

If you think of a CCR in simple terms you have the following parts
Can-literally a tube made out of various materials depending on the mfg. This will never "expire"
Scrubber-same as the can though some units use disposable scrubbers. Those units I believe all now have a packable scrubber option as well
Counterlungs-same as your wing. These will wear out eventually, but replacements are basically universal so you don't really have to worry about that. Aftermarket options are abound for most of the units, but it's literally the same concept as your wing, so even if a manufacturer goes defunct, you can build your own or scrounge from another unit
Loop hoses-same as the corrugated hose on your inflator albeit larger diameter. These will wear out eventually, but replacements are universal
DSV/BOV-same as your regulator, and also largely universal. Not a whole lot going on inside of them other than some mushroom valves *same concept as the exhaust diaphragms in your regulator*, and if it's a BOV odds are it uses standard regulator parts. People move these around regularly and adapters are available for different hose sizes, not a whole lot of complication there.
Electronics-all CCR's have them, some SCR's do not. This can be as simple as analog cell monitoring like the KISS units *3 analog o2 cells that send a voltage to a monitor of some sort*, or all the way up to super complicated eCCR redundant systems like the Liberty which has 2 solenoids, 4 o2 sensors, 2 he sensors, ambient and internal pressure sensors, a buddy light, and redundant main computers all inside of the head that read out to a buddy light and a pair of handsets.
Units like the KISS have no lifespan. If you want a new computer because your old one dies, you just go get another one. If it has a fischer cable it's as simple as plugging it in, if it is hardwired it's a bit more complicated but still doesn't take more than an hour or two depending on your soldering skills. As of now, that computer can accept anything from Shearwater, OSTC, Poseidon, DiveSoft, and a myriad of other computers that have cell monitoring ability. Most of the eCCR's on the market are now running on the DiveCAN from Shearwater so as long as Shearwater is in business, you have support from the manufacturer. If they go out, unfortunately you would then have to get a head replacement which is the expensive part of the rebreather. Same with Liberty, Poseidon, Hollis Explorer, etc etc. Most of the JMI units can be stripped out and converted to mCCR really easily so old Meg's, O2ptimas, etc that have those, if they fail, you can just remove them and the solenoid and put analog monitoring in them, same with the Revo's.

I'm sure I missed something, but basically most of the units can always be reverted to an mCCR which means they have an indefinite lifespan aside from the normal parts that will wear out with age. The ones that can't, are limited essentially by their electronics which can normally be upgraded

 

[mdax]

It doesn't matter if someone is told that rebreathers make the most sense for people doing deep dives.
There are people who have to have the coolest toys. They have to reach the "pinnacle" of diving.

Very few folks are pushing going slow or have a financial interest in divers following that path.

 

[Fransw]

I'm new to scuba and must still do my open water training. That said, can I start with a rebreather with no other scuba experience? And what is the refill limitations on the rebreather? In other words can I use it anywhere the same as with open circuit?

This must be silly questions!...sorry for that..

 

[RainPilot]

You can do all your training on a rebreather through RAID from OW and on. Barry Coleman is a co-owner of RAID and he is there on the SA East Coast near Aliwal Shoals I believe.

As far as gas fills go yes anywhere that can give you O2 and air will work, getting adsorbent is a little more specialist but no big hassle.

Learn to scuba dive | Get your scuba certification | Scuba diving lessons | Online scuba training | Learn to dive rebreathers | Scuba diving schools | Scuba vacations | Underwater photography | Diver training program


This course combines an OC OW course with a CCR OW course.

 

[tbone1004]

I'm new to scuba and must still do my open water training. That said, can I start with a rebreather with no other scuba experience? And what is the refill limitations on the rebreather? In other words can I use it anywhere the same as with open circuit?

This must be silly questions!...sorry for that..

yes you can start on a ccr with no experience. You are very limited in the types of units you can start on though. Poseidon is one of the few. I can't remember which agencies or instructors will authorize it though, it is very much not recommended by most people. When you have to bail out from a CCR you revert to an OC diver, and if you don't have any OC experience it can get a bit weird. You also need basically all of the same gear for OC as you do CCR, so if you start with a bp/w and proper regulators, the only thing you'll need to change is maybe the wing and a couple hose lengths when you make the switch. It's not like any OW gear is going to get wasted if you buy it properly from the start

 

[Fransw]

Thank you guys. RP, yes I heard about Barry. Also some guys with the Poseidon 7's here.. T-bone, yes from a safety point of view it makes sence to have some OC experience. I think I will do at least my OW on OC..cheers!

 

[stuartv]

As far as gas fills go yes anywhere that can give you O2 and air will work, getting adsorbent is a little more specialist but no big hassle.

I think you kind of glossed over that a bit. There are places I go regularly - popular places in NC - where you can't get an O2 fill (without a drive that can be short or long depending on specifically where you are) and/or you can't buy sorb. Pre-planning of logistics is definitely more important with a CCR than if you're diving OC where you really only HAVE to find someone with a basic scuba compressor.

 

[kensuf]

OMG. To the guy asking about starting with a CCR. Start with OC first, and get some experience please before making a jump to CCR. If your CCR fails you will go to OC for bailout, so you need to have experience knowing how that stuff works.

As for the post on the previous page about "how long will a CCR last???".. I dove an old KISS Classic for a year and a half until last October when I moved to a modern eCCR (SF2!). That KISS was as basic as you could possibly find, the design was from 1998 and that particular unit had a born on date of 2003. I jokingly said I could rebuild the unit from parts readily available at my local Home Depot or REI.

That particular unit is now 14 years old, I logged 240 hours on it and did dozens of dives below 150', it did everything I asked of it. I did dives up to 7 hours in length on that KISS, depths down to 300', and linear penetrations as far as 2 miles from the nearest air source. It was fine. I dove with the current owner of that unit a week ago, and it's still in service.

Although the SF2 I'm now diving is substantially superior in a number of ways, the only reason I moved on from the KISS was because the KISS was not very water tolerant, and I wanted something that I would be able to de-water when I was 2 miles from the nearest air source.

The point I'm making is that a well designed unit will last a very long time if properly maintained. It may not have the bells and whistles of units that come out in the future, but it will provide years of diving.

 

[michaelbd]

there are still original inspirations that are doing quite well in the field. 20+ years later. The electronics are considered obsolete, but you can always run in mCCR mode or convert to newer electronics
O2ptimas are right around a decade old and there are still many originals in the field. Most have been converted to the new DiveCAN from Shearwater, but the unit itself is still quite old.
You still see gen1 megs from time to time, though their support will be ending here shortly on the electronics front.

If you think of a CCR in simple terms you have the following parts
Can-literally a tube made out of various materials depending on the mfg. This will never "expire"
Scrubber-same as the can though some units use disposable scrubbers. Those units I believe all now have a packable scrubber option as well
Counterlungs-same as your wing. These will wear out eventually, but replacements are basically universal so you don't really have to worry about that. Aftermarket options are abound for most of the units, but it's literally the same concept as your wing, so even if a manufacturer goes defunct, you can build your own or scrounge from another unit
Loop hoses-same as the corrugated hose on your inflator albeit larger diameter. These will wear out eventually, but replacements are universal
DSV/BOV-same as your regulator, and also largely universal. Not a whole lot going on inside of them other than some mushroom valves *same concept as the exhaust diaphragms in your regulator*, and if it's a BOV odds are it uses standard regulator parts. People move these around regularly and adapters are available for different hose sizes, not a whole lot of complication there.
Electronics-all CCR's have them, some SCR's do not. This can be as simple as analog cell monitoring like the KISS units *3 analog o2 cells that send a voltage to a monitor of some sort*, or all the way up to super complicated eCCR redundant systems like the Liberty which has 2 solenoids, 4 o2 sensors, 2 he sensors, ambient and internal pressure sensors, a buddy light, and redundant main computers all inside of the head that read out to a buddy light and a pair of handsets.
Units like the KISS have no lifespan. If you want a new computer because your old one dies, you just go get another one. If it has a fischer cable it's as simple as plugging it in, if it is hardwired it's a bit more complicated but still doesn't take more than an hour or two depending on your soldering skills. As of now, that computer can accept anything from Shearwater, OSTC, Poseidon, DiveSoft, and a myriad of other computers that have cell monitoring ability. Most of the eCCR's on the market are now running on the DiveCAN from Shearwater so as long as Shearwater is in business, you have support from the manufacturer. If they go out, unfortunately you would then have to get a head replacement which is the expensive part of the rebreather. Same with Liberty, Poseidon, Hollis Explorer, etc etc. Most of the JMI units can be stripped out and converted to mCCR really easily so old Meg's, O2ptimas, etc that have those, if they fail, you can just remove them and the solenoid and put analog monitoring in them, same with the Revo's.

I'm sure I missed something, but basically most of the units can always be reverted to an mCCR which means they have an indefinite lifespan aside from the normal parts that will wear out with age. The ones that can't, are limited essentially by their electronics which can normally be upgraded

Wow thanks for the info tbone1004 and kensuf and rainpilot. I really appreciate you taking time to thoroughly explain everything. I really learnt a lot from your replies and have a much better picture now.

So... which CCR is the best? I'm just kidding!