Yong Heng compressor + breathing air filtering

[PBcatfish]

So then, grade E is the standard that should be adhered to? That is one good piece of information for me.

Are you saying that on a new $2,700 compressor, I can just trust the quality of the air it puts out? That would seem like quite the leap of faith to me.

 

[rcontrera]

Air from ANY compressor is a leap of faith. But, I have sold several hundred of these. And, for those that followed my advice on maintenance and service, they are still putting out grade E air.

 

[PBcatfish]

Air from ANY compressor is a leap of faith. But, I have sold several hundred of these. And, for those that followed my advice on maintenance and service, they are still putting out grade E air.

That being the case, your $2,700 compressor would certainly seem to be a viable option. It is an option that I am interested in learning more about. At this time, I would like to know the recommended maintenance actions & intervals, as well as their cost. My end purpose is to calculate those costs on a per-tank-filled basis so that I can then calculate my all-in cost of filling a tank. If those numbers work out, then I would want to find out the brand/model number & other particulars of the equipment that you are recommending. If you have already sold hundreds of these, then there is a very good chance that your equipment will be a good option & may well be the one that I end up choosing.

That aside, I am still interested in learning what the shortfalls of the cheap little 2-stage Chinese pump are. Hearing people say that they will run hot, burn oil & poison people, is cause for concern, but it is not empirical evidence. If I find that someone ran one for x-number of hours & then tested the air & found it to contain an undesirable level of contamination, that would be a different story. At that point, I would then want to investigate if running it more slowly &/or improving the cooling system may provide acceptable purity. The earlier assertions about those things producing dangerous gas may be spot-on correct, but until actual tests are performed, I consider that to be conjecture. It may be conjecture based on well founded experience. It may end up being correct. But until I see actual data, it is still just conjecture at this time. It's an untested hypothesis.

I am not saying that I want to bottle up a bunch of gas from the little cheap thing & go blindly suck it down at depth. I would however, be interested to see if there is a way to make them run so that they can produce an output that reliably tests as good. At this point, that is asking a lot, especially since I do not have a way to test the quality of the gas. So, for now, I am just left to ask questions & try to learn a little more. For now, it's more of a brain teaser for me, rather than an actual project to be prototyped.

Another concern with the cheap little Chinese pump would be longevity. If you fill 20-30 tanks, then the thing is worn out or broken, that would erase it's economical benefit. At this time, I don't even know if it's cylinders are sleeved or not. I'm guessing not, but I don't know.

Your $2,700 compressor, on the other hand, is an actual option at this time, if I can get more information about it.

Thanks

 

[TrimixToo]

That being the case, your $2,700 compressor would certainly seem to be a viable option. It is an option that I am interested in learning more about. At this time, I would like to know the recommended maintenance actions & intervals, as well as their cost. My end purpose is to calculate those costs on a per-tank-filled basis so that I can then calculate my all-in cost of filling a tank. If those numbers work out, then I would want to find out the brand/model number & other particulars of the equipment that you are recommending. If you have already sold hundreds of these, then there is a very good chance that your equipment will be a good option & may well be the one that I end up choosing.

That aside, I am still interested in learning what the shortfalls of the cheap little 2-stage Chinese pump are. Hearing people say that they will run hot, burn oil & poison people, is cause for concern, but it is not empirical evidence. If I find that someone ran one for x-number of hours & then tested the air & found it to contain an undesirable level of contamination, that would be a different story. At that point, I would then want to investigate if running it more slowly &/or improving the cooling system may provide acceptable purity. The earlier assertions about those things producing dangerous gas may be spot-on correct, but until actual tests are performed, I consider that to be conjecture. It may be conjecture based on well founded experience. It may end up being correct. But until I see actual data, it is still just conjecture at this time. It's an untested hypothesis.

I am not saying that I want to bottle up a bunch of gas from the little cheap thing & go blindly suck it down at depth. I would however, be interested to see if there is a way to make them run so that they can produce an output that reliably tests as good. At this point, that is asking a lot, especially since I do not have a way to test the quality of the gas. So, for now, I am just left to ask questions & try to learn a little more. For now, it's more of a brain teaser for me, rather than an actual project to be prototyped.

Another concern with the cheap little Chinese pump would be longevity. If you fill 20-30 tanks, then the thing is worn out or broken, that would erase it's economical benefit. At this time, I don't even know if it's cylinders are sleeved or not. I'm guessing not, but I don't know.

Your $2,700 compressor, on the other hand, is an actual option at this time, if I can get more information about it.

Thanks

You are, of course, free to be a test pilot.

However, there are substantial advantages to proven designs for aviation and diving both. It's literally your life at stake, and there is no experiential base to assure you that the probability the thing will stay clean is high between air tests performed with any reasonable frequency. Worse, there are reasons to believe it is or could become unsafe without warning.

Heck, I have a K14 with three full-size filter towers and I'm reluctant to give friends air. It's not because I don't believe it's OK or I'm that cheap (actually I'd like to to run more hours a year than it does), but because I'm not really insured for that. One of my favorite bumper stickers is, "Do-do occurs." Despite my best efforts, things can still go wrong...but I find the risk of breathing air (and other mixes) from my system low enough to accept.

 

[RayfromTX]

If your friend or acquaintance dies while diving your air is it going to matter much what went wrong or is it possible that you will be defending yourself anyway from the estate of the deceased.

 

[TrimixToo]

If your friend or acquaintance dies while diving your air is it going to matter much what went wrong or is it possible that you will be defending yourself anyway from the estate of the deceased.

What went wrong would matter very much, to me; more than nearly anything else, in fact. I would have a deep need to know what happened.

However, I don't want to be in that position to begin with. I also don't want to breath gas I'm not pretty sure about.

 

[RayfromTX]

I didn't mean to be obtuse. I meant that it may not matter if your air had anything to do with a diving accident. If there is a questionable nature to the accident, they may investigate the source of the fill and you may end up defending yourself.

I think you and I fill our own tanks for many of the same reasons.

 

[rcontrera]

The little $2700 MCH6 is kind of expensive to operate. It will cost about $1 per fill for the filter cartridge, about $1 for 100 hour valve service and about $ 0.15 per fill for oil and a few cents per fill for gas or electricity. A few years ago I had figured you were going to spend $2.90 per fill without figuring the actual cost of the compressor. I didn't figure out the cost since it really depends on how you take care of your compressor. It is possible to trash a compressor in just a couple of years. It is also possible to take care of your compressor and have it last longer than you will still have interest in diving. I have a customer that has had his MCH6 ten years longer than I have been selling them ... since 1985.

 

[PBcatfish]

The little $2700 MCH6 is kind of expensive to operate. It will cost about $1 per fill for the filter cartridge, about $1 for 100 hour valve service and about $ 0.15 per fill for oil and a few cents per fill for gas or electricity. A few years ago I had figured you were going to spend $2.90 per fill without figuring the actual cost of the compressor. I didn't figure out the cost since it really depends on how you take care of your compressor. It is possible to trash a compressor in just a couple of years. It is also possible to take care of your compressor and have it last longer than you will still have interest in diving. I have a customer that has had his MCH6 ten years longer than I have been selling them ... since 1985.

Thank you for saving me the time of doing the math myself. At $3/fill, this is a viable project & warrants further investigation.

 

[TrimixToo]

Thank you for saving me the time of doing the math myself. At $3/fill, this is a viable project & warrants further investigation.

Where owning your own fill station really shines is when you start to dive mixes other than air. Trimix, in particular (assuming here that the current He shortage is not permanent), is far less expensive if you mix it yourself instead of buying it, but even nitrox is markedly cheaper to blend than to buy. You do have to factor your time into the equation, though, and for trimix you'll want a booster (there's one for sale on the board for a decent price right now!). There are additional costs for hoses, fittings, good gauges...

If I only dove air, the club compressor or LDS would serve just fine.